SEKIGUCHI Fumiko

Researcher Information

Degree

• Ph.D.（Kinki University）

URL

http://www.phar.kindai.ac.jp/byoutai/

J-Global ID

• 200901040664676800

Research Interests

• HMGB1   neuropathic pain   hydrogen sulfide   T-type calcium channel   プロテアーゼ活性化受容体   Protection of gastic mucosa   Protease-activated receptor   

Research Areas

• Life sciences / Pharmacology

Academic & Professional Experience

• 2008/04 - Today  Kinki University School of PharmacyPharmacology and PathophysiologyAssociate Professor
• 2007/04 - 2008/03  Kinki University School of PharmacyPharmacology and Pathophysiologylecturer
• 2003/04 - 2007/03  Kindai UniversityFaculty of Pharmacy
• 2002/04 - 2003/03  Kindai UniversityFaculty of Pharmacy
• 2002 - 2003  Assistant Professor, Dept. Anat. and Physiol.,
• 2003  - Assistant Professor, Div. Phisio. and Pathophysiol.,
• 1991/04 - 2002/03  Kindai UniversityFaculty of Pharmacy
• 1991 - 2002  Instructor, Dept. Anat. and Physiol.,
• Sch. Pharmaceu. Sci., Kinki Univ.
• Sch. Pharmaceu. Sci., Kinki Univ.
• Sch. Pharmaceu. Sci., Kinki Univ.

Education

•        - 1991  The University of Tokushima  Faculty of Pharmaceutical Sciences  School of Pharmacy
•        - 1991  The University of Tokushima  School of Pharmaceutical Sciences

Association Memberships

• Society for Neuroscience   日本疼痛学会   日本薬学会   日本平滑筋学会   日本薬理学会   

Published Papers

• Cav3.2-dependent hyperalgesia/allodynia following intrathecal and intraplantar zinc chelator administration in rodents.

  Shiori Tomita; Fumiko Sekiguchi; Katsuki Naoe; Shiyu Shikimi; Yoshihito Kasanami; Maya Ohigashi; Maho Tsubota; Atsufumi Kawabata

  Journal of pharmacological sciences 152 (2) 86 - 89 2023/06 

  Cav3.2, a T-type calcium channel (T-channel) family member, is expressed in the nociceptors and spinal cord, and its activity is largely suppressed by zinc under physiological conditions. In rats, intrathecal and intraplantar administration of a zinc chelator, TPEN, caused T-channel-dependent mechanical hyperalgesia, and the intraplantar, but not intrathecal, TPEN induced Cav3.2 upregulation in the dorsal root ganglion. In mice, intraplantar TPEN also caused mechanical allodynia, which was abolished by T-channel inhibitors or Cav3.2 gene deletion. Together, spinal and peripheral zinc deficiency appears to enhance Cav3.2 activity in the spinal postsynaptic neurons and nociceptors, respectively, thereby promoting pain.
• A hydrolysate of poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) suppresses Cav3.2-dependent pain by sequestering exogenous and endogenous sulfide.

  Fumiko Sekiguchi; Nene Koike; Yasuhiro Shimada; Kaho Sugimoto; Hiroshi Masuda; Takashi Nakamura; Hiroaki Yamaguchi; Genzoh Tanabe; Shinsuke Marumoto; Yoshihito Kasanami; Maho Tsubota; Tsuyako Ohkubo; Shigeru Yoshida; Atsufumi Kawabata

  Redox biology 59 102579 - 102579 2023/02 

  Poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132), an organogermanium, is hydrolyzed to 3-(trihydroxygermyl)propanoic acid (THGP) in aqueous solutions, and reduces inflammation, pain and cancer, whereas the underlying mechanisms remain unknown. Sulfides including H2S, a gasotransmitter, generated from l-cysteine by some enzymes including cystathionine-γ-lyase (CSE), are pro-nociceptive, since they enhance Cav3.2 T-type Ca2+ channel activity expressed in the primary afferents, most probably by canceling the channel inhibition by Zn2+ linked via coordinate bonding to His191 of Cav3.2. Given that germanium is reactive to sulfur, we tested whether THGP would directly trap sulfide, and inhibit sulfide-induced enhancement of Cav3.2 activity and sulfide-dependent pain in mice. Using mass spectrometry and 1H NMR techniques, we demonstrated that THGP directly reacted with sulfides including Na2S and NaSH, and formed a sulfur-containing reaction product, which decreased in the presence of ZnCl2. In Cav3.2-transfected HEK293 cells, THGP inhibited the sulfide-induced enhancement of T-type Ca2+ channel-dependent membrane currents. In mice, THGP, administered systemically or locally, inhibited the mechanical allodynia caused by intraplantar Na2S. In the mice with cyclophosphamide-induced cystitis and cerulein-induced pancreatitis, which exhibited upregulation of CSE in the bladder and pancreas, respectively, systemic administration of THGP as well as a selective T-type Ca2+ channel inhibitor suppressed the cystitis-related and pancreatitis-related visceral pain. These data suggest that THGP traps sulfide and inhibits sulfide-induced enhancement of Cav3.2 activity, leading to suppression of Cav3.2-dependent pain caused by sulfide applied exogenously and generated endogenously.
• Opioid modulation of T-type Ca2+ channel-dependent neuritogenesis/neurite outgrowth through the prostaglandin E2/EP4 receptor/protein kinase A pathway in mouse dorsal root ganglion neurons.

  Takashi Maeda; Fumiko Sekiguchi; Kenji Mitani; Ryosuke Yamagata; Maho Tsubota; Shigeru Yoshida; Atsufumi Kawabata

  Biochemical and biophysical research communications 639 142 - 149 2023/01 

  Irregular regeneration or inappropriate remodeling of the axons of the primary afferent neurons after peripheral nerve trauma could be associated with the development of neuropathic pain. We analyzed the molecular mechanisms for the neuritogenesis and neurite outgrowth caused by prostaglandin E2 (PGE2) in mouse dorsal root ganglion (DRG) neurons, and evaluated their opioid modulation. PGE2 in combination with IBMX, a phosphodiesterase inhibitor, caused neuritogenesis/neurite outgrowth in DRG cells, an effect abolished by a prostanoid EP4, but not EP2, receptor antagonist, and inhibitors of adenylyl cyclase or protein kinase A (PKA). Blockers of T-type Ca2+ channels (T-channels), that are responsible for window currents involving the sustained low-level Ca2+ entry at voltages near the resting membrane potentials and can be functionally upregulated by PKA, inhibited the neuritogenesis/neurite outgrowth caused by PGE2/IBMX or dibutylyl cyclic AMP, a PKA activator, in DRG neurons, an inhibitory effect mimicked by ZnCl2 and ascorbic acid that block Cav3.2, but not Cav3.1 or Cav3.3, T-channels. Morphine and DAMGO, μ-opioid receptor (MOR) agonists, suppressed the neuritogenesis and/or neurite outgrowth induced by PGE2/IBMX in DRG neurons and also DRG neuron-like ND7/23 cells, an effect reversed by naloxone or β-funaltrexamine, a selective MOR antagonist. Our data suggest that the EP4 receptor/PKA/Cav3.2 pathway is involved in the PGE2-induced neuritogenesis/neurite outgrowth in DRG neurons, which can be suppressed by MOR stimulation. We propose that MOR agonists including morphine in the early phase after peripheral nerve trauma might delay the axonal regeneration of the primary afferent neurons but prevent the development of neuropathic pain.
• Dietary Zinc Deficiency Induces Cav3.2-Dependent Nociceptive Hypersensitivity in Mice.

  Shiori Tomita; Fumiko Sekiguchi; Maho Tsubota; Atsufumi Kawabata

  Biological & pharmaceutical bulletin 46 (9) 1343 - 1346 2023 

  Cav3.2 channels belong to the T-type calcium channel (T-channel) family, i.e., low voltage-activated calcium channels, and are abundantly expressed in the nociceptors, playing a principal role in the development of pathological pain. The channel activity of Cav3.2 is suppressed by zinc under physiological conditions. We thus tested whether dietary zinc deficiency would cause Cav3.2-dependent nociceptive hypersensitivity in mice. In the mice fed with zinc deficient diet for 2 weeks, plasma zinc levels declined by more than half, and mechanical allodynia developed. The dietary zinc deficiency-induced allodynia was restored by T-channel inhibitors or by Cav3.2 gene silencing. These data demonstrate that zinc deficiency induces Cav3.2-dependent nociceptive hypersensitivity in mice, thereby suggesting that pain experienced by patients with diseases accompanied by zinc deficiency (e.g., chronic kidney disease) might involve the increased Cav3.2 activity.
• Development of hepatic impairment aggravates chemotherapy-induced peripheral neuropathy following oxaliplatin treatment: Evidence from clinical and preclinical studies

  Tomoyoshi Miyamoto; Risa Domoto; Fumiko Sekiguchi; Riki Kamaguchi; Rika Nishimura; Misato Matsuno; Maho Tsubota; Masanori Fujitani; Shigekatsu Hatanaka; Yuichi Koizumi; Dengli Wang; Masahiro Nishibori; Atsufumi Kawabata

  Journal of Pharmacological Sciences Elsevier BV 148 (3) 315 - 325 1347-8613 2022/03 [Refereed]
  
• Discovery of Pimozide Derivatives as Novel T-type Calcium Channel Inhibitors with Little Binding Affinity to Dopamine D2 Receptors for Treatment of Somatic and Visceral Pain

  Yoshihito Kasanami; Chihiro Ishikawa; Takahiro Kino; Momoka Chonan; Naoki Toyooka; Yasuhiro Takashima; Yuriko Iba; Fumiko Sekiguchi; Maho Tsubota; Tsuyako Ohkubo; Shigeru Yoshida; Takuya Okada; Atsufumi Kawabata

  European Journal of Medicinal Chemistry in press 114716 - 114716 2022 [Refereed]
   

  T-type Ca2+ channels (T-channels), particularly Cav3.2 and Cav3.1 isoforms, are promising targets for treating various diseases including intractable pain. Given the potent inhibitory activity of pimozide, an antipsychotic, against T-channels, we conducted structure-activity relationship studies of pimozide derivatives, and identified several compounds including 3a, 3s, and 4 that had potency comparable to that of pimozide in inhibiting T-channels, but little binding affinity to dopamine D2 receptors. The introduction of a phenylbutyl group on the benzoimidazole nuclei of pimozide was considered a key structural modification to reduce the binding affinity to D2 receptors. Those pimozide derivatives potently suppressed T-channel-dependent somatic and visceral pain in mice, without causing any motor dysfunctions attributable to D2 receptor blockade, including catalepsy. The present study thus provides an avenue to develop novel selective T-channel inhibitors available for pain management via the structural modification of existing medicines.
• Role of neuron-derived ATP in paclitaxel-induced HMGB1 release from macrophages and peripheral neuropathy.

  Risa Domoto; Fumiko Sekiguchi; Riki Kamaguchi; Maiko Iemura; Hiroki Yamanishi; Maho Tsubota; Dengli Wang; Masahiro Nishibori; Atsufumi Kawabata

  Journal of pharmacological sciences 148 (1) 156 - 161 2022/01 [Refereed]
   

  We examined the role of ATP and high mobility group box 1 (HMGB1) in paclitaxel-induced peripheral neuropathy (PIPN). PIPN in mice was prevented by HMGB1 neutralization, macrophage depletion, and P2X7 or P2X4 blockade. Paclitaxel and ATP synergistically released HMGB1 from macrophage-like RAW264.7 cells, but not neuron-like NG108-15 cells. The paclitaxel-induced HMGB1 release from RAW264.7 cells was accelerated by co-culture with NG108-15 cells in a manner dependent on P2X7 or P2X4. Paclitaxel released ATP from NG108-15 cells, but not RAW264.7 cells. Thus, PIPN is considered to involve acceleration of HMGB1 release from macrophages through P2X7 and P2X4 activation by neuron-derived ATP.
• Caspase-Dependent HMGB1 Release from Macrophages Participates in Peripheral Neuropathy Caused by Bortezomib, a Proteasome-Inhibiting Chemotherapeutic Agent, in Mice.

  Maho Tsubota; Takaya Miyazaki; Yuya Ikeda; Yusuke Hayashi; Yui Aokiba; Shiori Tomita; Fumiko Sekiguchi; Dengli Wang; Masahiro Nishibori; Atsufumi Kawabata

  Cells 10 (10) 2021/09 [Refereed]
   

  Given the role of macrophage-derived high mobility group box 1 (HMGB1) in chemotherapy-induced peripheral neuropathy (CIPN) caused by paclitaxel, we analyzed the role of HMGB1 and macrophages in the CIPN caused by bortezomib, a proteasome-inhibiting chemotherapeutic agent used for the treatment of multiple myeloma. Repeated administration of bortezomib caused CIPN accompanied by early-stage macrophage accumulation in the dorsal root ganglion. This CIPN was prevented by an anti-HMGB1-neutralizing antibody, thrombomodulin alfa capable of accelerating thrombin-dependent degradation of HMGB1, antagonists of the receptor for advanced glycation end-products (RAGE) and C-X-C motif chemokine receptor 4 (CXCR4), known as HMGB1-targeted membrane receptors, or macrophage depletion with liposomal clodronate, as reported in a CIPN model caused by paclitaxel. In macrophage-like RAW264.7 cells, bortezomib as well as MG132, a well-known proteasome inhibitor, caused HMGB1 release, an effect inhibited by caspase inhibitors but not inhibitors of NF-κB and p38 MAP kinase, known to mediate paclitaxel-induced HMGB1 release from macrophages. Bortezomib increased cleaved products of caspase-8 and caused nuclear fragmentation or condensation in macrophages. Repeated treatment with the caspase inhibitor prevented CIPN caused by bortezomib in mice. Our findings suggest that bortezomib causes caspase-dependent release of HMGB1 from macrophages, leading to the development of CIPN via activation of RAGE and CXCR4.
• Macrophage as a Peripheral Pain Regulator.

  Risa Domoto; Fumiko Sekiguchi; Maho Tsubota; Atsufumi Kawabata

  Cells 10 (8) 2021/07 [Refereed]
   

  A neuroimmune crosstalk is involved in somatic and visceral pathological pain including inflammatory and neuropathic components. Apart from microglia essential for spinal and supraspinal pain processing, the interaction of bone marrow-derived infiltrating macrophages and/or tissue-resident macrophages with the primary afferent neurons regulates pain signals in the peripheral tissue. Recent studies have uncovered previously unknown characteristics of tissue-resident macrophages, such as their origins and association with regulation of pain signals. Peripheral nerve macrophages and intestinal resident macrophages, in addition to adult monocyte-derived infiltrating macrophages, secrete a variety of mediators, such as tumor necrosis factor-α, interleukin (IL)-1β, IL-6, high mobility group box 1 and bone morphogenic protein 2 (BMP2), that regulate the excitability of the primary afferents. Neuron-derived mediators including neuropeptides, ATP and macrophage-colony stimulating factor regulate the activity or polarization of diverse macrophages. Thus, macrophages have multitasks in homeostatic conditions and participate in somatic and visceral pathological pain by interacting with neurons.
• Estrogen decline is a risk factor for paclitaxel-induced peripheral neuropathy: Clinical evidence supported by a preclinical study.

  Tomoyoshi Miyamoto; Shiori Hiramoto; Ayano Kanto; Maho Tsubota; Masanori Fujitani; Hiroki Fukuyama; Shigekatsu Hatanaka; Fumiko Sekiguchi; Yuichi Koizumi; Atsufumi Kawabata

  Journal of pharmacological sciences 146 (1) 49 - 57 2021/05 [Refereed]
   

  We performed clinical retrospective study in female cancer patients and fundamental experiments in mice, in order to clarify risk factors for paclitaxel-induced peripheral neuropathy (PIPN). In the clinical study, 131 of 189 female outpatients with cancer undergoing paclitaxel-based chemotherapy met inclusion criteria. Breast cancer survivors (n = 40) showed significantly higher overall PIPN (grades 1-4) incidence than non-breast cancer survivors (n = 91). Multivariate sub-analyses of breast cancer survivors showed that 57 years of age or older and endocrine therapy before paclitaxel treatment were significantly associated with severe PIPN (grades 2-4). The age limit was also significantly correlated with overall development of severe PIPN. In the preclinical study, female mice subjected to ovariectomy received repeated administration of paclitaxel, and mechanical nociceptive threshold was assessed by von Frey test. Ovariectomy aggravated PIPN in the mice, an effect prevented by repeated treatment with 17β-estradiol. Repeated administration of thrombomodulin alfa (TMα), known to prevent chemotherapy-induced peripheral neuropathy in rats and mice, also prevented the development of PIPN in the ovariectomized mice. Collectively, breast cancer survivors, particularly with postmenopausal estrogen decline and/or undergoing endocrine therapy, are considered a PIPN-prone subpopulation, and may require non-hormonal pharmacological intervention for PIPN in which TMα may serve as a major candidate.
• Corrigendum to "Essential role of Cav3.2 T-type calcium channels in butyrate-induced colonic pain and nociceptor hypersensitivity in mice" [Eur. J. Pharmacol. 887 (2020) 173576].

  Maho Tsubota; Kazuki Matsui; Maki Nakano; Rie Kajitani; Yuko Ishii; Ken Tomochika; Yuta Nishikawa; Saaya Fukushi; Ayumu Yamagata; Fumiko Sekiguchi; Takuya Okada; Naoki Toyooka; Atsufumi Kawabata

  European journal of pharmacology 892 173795 - 173795 2021/02 [Refereed]
  
• Effects of Bepridil and Pimozide, Existing Medicines Capable of Blocking T-Type Ca2+ Channels, on Visceral Pain in Mice.

  Maho Tsubota; Kazuki Matsui; Saaya Fukushi; Kyoko Okazaki; Fumiko Sekiguchi; Atsufumi Kawabata

  Biological & pharmaceutical bulletin 44 (3) 461 - 464 2021 [Refereed]
   

  T-Type Ca2+ channels (T-channels), particularly Cav3.2, are now considered as therapeutic targets for treatment of intractable pain including visceral pain. Among existing medicines, bepridil, a multi-channel blocker, used for treatment of arrhythmia and angina, and pimozide, a dopamine D2 receptor antagonist, known as a typical antipsychotic, have potent T-channel blocking activity. We thus tested whether bepridil and pimozide could suppress visceral pain in mice. Colonic and bladder pain were induced by intracolonic administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) and systemic administration of cyclophosphamide (CPA), respectively. Referred hyperalgesia was assessed by von Frey test, and colonic hypersensitivity to distension by a volume load with intracolonic water injection and spontaneous bladder pain were evaluated by observing nociceptive behaviors in conscious mice. The mice exhibited referred hyperalgesia and colonic hypersensitivity to distension on day 6 after TNBS treatment. Systemic administration of bepridil at 10-20 mg/kg or pimozide at 0.1-0.5 mg/kg strongly reduced the referred hyperalgesia on the TNBS-induced referred hyperalgesia and colonic hypersensitivity to distension. CPA treatment caused bladder pain-like nociceptive behavior and referred hyperalgesia, which were reversed by bepridil at 10-20 mg/kg or pimozide at 0.5-1 mg/kg. Our data thus suggest that bepridil and pimozide, existing medicines capable of blocking T-channels, are useful for treatment of colonic and bladder pain, and serve as seeds for the development of new medicines for visceral pain treatment.
• Role of HMGB1 in Chemotherapy-Induced Peripheral Neuropathy.

  Fumiko Sekiguchi; Atsufumi Kawabata

  International journal of molecular sciences 22 (1) 2020/12 [Refereed]
   

  Chemotherapy-induced peripheral neuropathy (CIPN), one of major dose-limiting side effects of first-line chemotherapeutic agents such as paclitaxel, oxaliplatin, vincristine, and bortezomib is resistant to most of existing medicines. The molecular mechanisms of CIPN have not been fully understood. High mobility group box 1 (HMGB1), a nuclear protein, is a damage-associated molecular pattern protein now considered to function as a pro-nociceptive mediator once released to the extracellular space. Most interestingly, HMGB1 plays a key role in the development of CIPN. Soluble thrombomodulin (TMα), known to degrade HMGB1 in a thrombin-dependent manner, prevents CIPN in rodents treated with paclitaxel, oxaliplatin, or vincristine and in patients with colorectal cancer undergoing oxaliplatin-based chemotherapy. In this review, we describe the role of HMGB1 and its upstream/downstream mechanisms in the development of CIPN and show drug candidates that inhibit the HMGB1 pathway, possibly useful for prevention of CIPN.
• Cav3.2 overexpression in L4 dorsal root ganglion neurons after L5 spinal nerve cutting involves Egr-1, USP5 and HMGB1 in rats: An emerging signaling pathway for neuropathic pain.

  Shiori Tomita; Fumiko Sekiguchi; Yoshihito Kasanami; Katsuki Naoe; Maho Tsubota; Hidenori Wake; Masahiro Nishibori; Atsufumi Kawabata

  European journal of pharmacology 888 173587 - 173587 2020/12 [Refereed]
   

  Overexpression of Cav3.2 T-type Ca2+ channels in L4 dorsal root ganglion (DRG) participates in neuropathic pain after L5 spinal nerve cutting (L5SNC) in rats. The L5SNC-induced neuropathic pain also involves high mobility group box 1 (HMGB1), a damage-associated molecular pattern protein, and its target, the receptor for advanced glycation end-products (RAGE). We thus studied the molecular mechanisms for the L5SNC-induced Cav3.2 overexpression as well as neuropathic pain in rats by focusing on; 1) possible involvement of early growth response 1 (Egr-1), known to regulate transcriptional expression of Cav3.2, and ubiquitin-specific protease 5 (USP5) that protects Cav3.2 from proteasomal degradation, and 2) possible role of HMGB1/RAGE as an upstream signal. Protein levels of Cav3.2 as well as Egr-1 in L4 DRG significantly increased in the early (day 6) and persistent (day 14) phases of neuropathy after L5SNC, while USP5 protein in L4 DRG did not increase on day 6, but day 14. An anti-HMGB1-neutralizing antibody or a low molecular weight heparin, a RAGE antagonist, prevented the development of neuropathic pain and upregulation of Egr-1 and Cav3.2 in L4 DRG after L5SNC. L5SNC increased macrophages accumulating in the sciatic nerves, and the cytoplasm/nuclear ratio of immunoreactive HMGB1 in those macrophages. Our findings suggest that L5SNC-induced Cav3.2 overexpression in L4 DRG and neuropathic pain involves Egr-1 upregulation downstream of the macrophage-derived HMGB1/RAGE pathway, and that the delayed upregulation of USP5 might contribute to the persistent Cav3.2 overexpression and neuropathy.
• Essential role of Cav3.2 T-type calcium channels in butyrate-induced colonic pain and nociceptor hypersensitivity in mice.

  Maho Tsubota; Kazuki Matsui; Maki Nakano; Rie Kajitani; Yuko Ishii; Ken Tomochika; Yuta Nishikawa; Saaya Fukushi; Ayumu Yamagata; Fumiko Sekiguchi; Takuya Okada; Naoki Toyooka; Atsufumi Kawabata

  European journal of pharmacology 887 173576 - 173576 2020/11 [Refereed]
   

  Given the role of Cav3.2 isoform among T-type Ca2+ channels (T-channels) in somatic and visceral nociceptive processing, we analyzed the contribution of Cav3.2 to butyrate-induced colonic pain and nociceptor hypersensitivity in mice, to evaluate whether Cav3.2 could serve as a target for treatment of visceral pain in irritable bowel syndrome (IBS) patients. Mice of ddY strain, and wild-type and Cav3.2-knockout mice of a C57BL/6J background received intracolonic administration of butyrate twice a day for 3 days. Referred hyperalgesia in the lower abdomen was assessed by von Frey test, and colonic hypersensitivity to distension by a volume load or chemicals was evaluated by counting nociceptive behaviors. Spinal phosphorylated ERK was detected by immunohistochemistry. Cav3.2 knockdown was accomplished by intrathecal injection of antisense oligodeoxynucleotides. Butyrate treatment caused referred hyperalgesia and colonic hypersensitivity to distension in ddY mice, which was abolished by T-channel blockers and/or Cav3.2 knockdown. Butyrate also increased the number of spinal phosphorylated ERK-positive neurons following colonic distension in the anesthetized ddY mice. The butyrate-treated ddY mice also exhibited T-channel-dependent colonic hypersensitivity to intracolonic Na2S, known to enhance Cav3.2 activity, and TRPV1, TRPA1 or proteinase-activated receptor 2 (PAR2) agonists. Wild-type, but not Cav3.2-knockout, mice of a C57BL/6J background, after treated with butyrate, mimicked the T-channel-dependent referred hyperalgesia and colonic hypersensitivity in butyrate-treated ddY mice. Our study provides definitive evidence for an essential role of Cav3.2 in the butyrate-induced colonic pain and nociceptor hypersensitivity, which might serve as a target for treatment of visceral pain in IBS patients.
• Role of high-mobility group box 1 and its modulation by thrombomodulin/thrombin axis in neuropathic and inflammatory pain.

  Ryuichi Tsujita; Maho Tsubota; Fumiko Sekiguchi; Atsufumi Kawabata

  British journal of pharmacology 178 (4) 798 - 812 2020/05 [Refereed]
   

  High-mobility group box 1 (HMGB1), a nuclear protein, once released to the extracellular space, facilitates pain signals as well as inflammation. Intraplantar or intraspinal application of HMGB1 elicits hyperalgesia/allodynia in rodents by activating the advanced glycosylation end-product specific receptor (receptor for advanced glycation end-products; RAGE) or Toll-like receptor 4 (TLR4). Endogenous HMGB1 derived from neurons, perineuronal cells or immune cells accumulating in the dorsal root ganglion or sensory nerves participates in somatic and visceral pain consisting of neuropathic and/or inflammatory components. Endothelial thrombomodulin (TM) and recombinant human soluble TM, TMα, markedly increase thrombin-dependent degradation of HMGB1, and systemic administration of TMα prevents and reverses various HMGB1-dependent pathological pain. Low MW compounds that directly inactivate HMGB1 or antagonize HMGB1-targeted receptors would be useful to reduce various forms of intractable pain. Thus, HMGB1 and its receptors are considered to serve as promising targets in developing novel agents to prevent or treat pathological pain.
• Genetic deletion of Cav3.2 T-type calcium channels abolishes H2S-dependent somatic and visceral pain signaling in C57BL/6 mice.

  Kazuki Matsui; Maho Tsubota; Saaya Fukushi; Nene Koike; Hiroshi Masuda; Yoshihito Kasanami; Takaya Miyazaki; Fumiko Sekiguchi; Tsuyako Ohkubo; Shigeru Yoshida; Yutaro Mukai; Akira Oita; Mitsutaka Takada; Atsufumi Kawabata

  Journal of pharmacological sciences 140 (3) 310 - 312 2019/07 [Refereed]
   

  We tested whether genetic deletion of Cav3.2 T-type Ca2+ channels abolishes hydrogen sulfide (H2S)-mediated pain signals in mice. In Cav3.2-expressing HEK293 cells, Na2S, an H2S donor, at 100 μM clearly increased Ba2+ currents, as assessed by whole-cell patch-clamp recordings. In wild-type C57BL/6 mice, intraplantar and intracolonic administration of Na2S evoked mechanical allodynia and visceral nociceptive behavior, respectively, which were abolished by TTA-A2, a T-type Ca2+ channel blocker. In Cav3.2-knockout mice of a C57BL/6 background, Na2S caused neither somatic allodynia nor colonic nociception. Our study thus provides definitive evidence for an essential role of Cav3.2 in H2S-dependent somatic and colonic pain.
• NNC 55-0396, a T-type calcium channel blocker, protects against the brain injury induced by middle cerebral artery occlusion and reperfusion in mice.

  Sachi Matsuda; Hiroyuki Nishikawa; Anna Fukatsu; Yuko Kurokawa; Maho Tsubota; Fumiko Sekiguchi; Shogo Tokuyama; Atsufumi Kawabata

  Journal of pharmacological sciences 140 (2) 193 - 196 2019/06 [Refereed]
   

  We tested whether NNC 55-0396 (NNC), a T-type calcium channel (T-channel) blocker, reduces the brain injury caused by middle cerebral artery occlusion and reperfusion (MCAO/R) in mice. NNC, administered i.c.v. before the occlusion, greatly reduced the MCAO/R-induced brain infarct and neurological dysfunctions, although it, given toward the end of occlusion, was less effective. Systemic administration of NNC before the occlusion also attenuated the infarct and neurological dysfunctions. Our data imply that blood-brain-barrier-permeable T-channel blockers such as NNC are capable of reducing MCAO/R-induced brain damage, and that T-channels are involved in neuronal damage induced by ischemia rather than reperfusion.
• Dietary ascorbic acid restriction in GNL/SMP30-knockout mice unveils the role of ascorbic acid in regulation of somatic and visceral pain sensitivity.

  Tsubota M; Uebo K; Miki K; Sekiguchi F; Ishigami A; Kawabata A

  Biochem Biophys Res Commun. 511 (3) 705 - 710 2019/03 [Refereed]
  
• Critical role of Cav3.2 T-type calcium channels in the peripheral neuropathy induced by bortezomib, a proteasome-inhibiting chemotherapeutic agent, in mice.

  Shiori Tomita; Fumiko Sekiguchi; Tomoyo Deguchi; Takaya Miyazaki; Yuya Ikeda; Maho Tsubota; Shigeru Yoshida; Huy Du Nguyen; Takuya Okada; Naoki Toyooka; Atsufumi Kawabata

  Toxicology 413 33 - 39 2019/02 [Refereed]
   

  Bortezomib, a first-line agent for treatment of multiple myeloma, exhibits anticancer activity through proteasome inhibition. However, bortezomib-induced peripheral neuropathy (BIPN) is one of the most serious side effects. Since decreased proteasomal degradation of Cav3.2 T-type calcium channels in the primary afferents is involved in persistent pain, we investigated whether BIPN involves increased protein levels of Cav3.2 in mice. Six repeated i.p. administrations of bortezomib for 12 days developed persistent mechanical allodynia. Systemic administration of novel T-type calcium channel blockers, (2R/S)-6-prenylnaringenin and KTt-45, and of TTA-A2, the well-known blocker, reversed the BIPN. Ascorbic acid, known to block Cav3.2, but not Cav3.1 or 3.3, and silencing of Cav3.2 gene also suppressed BIPN. Protein levels of Cav3.2 in the dorsal root ganglion (DRG) at L4-L6 levels increased throughout days 1-21 after the onset of bortezomib treatment. Protein levels of USP5, a deubiquitinating enzyme that specifically inhibits proteasomal degradation of Cav3.2, increased in DRG on days 3-21, but not day 1, in bortezomib-treated mice. In DRG-derived ND7/23 cells, bortezomib increased protein levels of Cav3.2 and T-channel-dependent currents, as assessed by a patch-clamp method, but did not upregulate expression of Cav3.2 mRNA or USP5 protein. MG-132, another proteasome inhibitor, also increased Cav3.2 protein levels in the cultured cells. Given the previous evidence for USP5 induction following nociceptor excitation, our data suggest that BIPN involves the increased protein levels of Cav3.2 in nociceptors through inhibition of proteasomal degradation of Cav3.2 by bortezomib itself and then by USP5 that is upregulated probably in an activity-dependent manner.
• Role of non-macrophage cell-derived HMGB1 in oxaliplatin-induced peripheral neuropathy and its prevention by the thrombin/thrombomodulin system in rodents: negative impact of anticoagulants.

  Maho Tsubota; Ryotaro Fukuda; Yusuke Hayashi; Takaya Miyazaki; Shin Ueda; Rika Yamashita; Nene Koike; Fumiko Sekiguchi; Hidenori Wake; Shuji Wakatsuki; Yuka Ujiie; Toshiyuki Araki; Masahiro Nishibori; Atsufumi Kawabata

  Journal of neuroinflammation 16 (1) 199 - 199 2019/10 [Refereed]
   

  BACKGROUND: Macrophage-derived high mobility group box 1 (HMGB1), a damage-associated molecular pattern (DAMP) protein, plays a key role in the development of chemotherapy-induced peripheral neuropathy (CIPN) caused by paclitaxel in rodents. Endothelial thrombomodulin (TM) promotes thrombin-induced degradation of HMGB1, and TMα, a recombinant human soluble TM, abolishes peripheral HMGB1-induced allodynia in mice. We thus examined whether HMGB1, particularly derived from macrophages, contributes to oxaliplatin-induced neuropathy in mice and analyzed the anti-neuropathic activity of the TM/thrombin system. METHODS: CIPN models were created by the administration of oxaliplatin in mice and rats, and the nociceptive threshold was assessed by von Frey test or paw pressure test. Macrophage-like RAW264.7 cells were stimulated with oxaliplatin in vitro. Proteins were detected and/or quantified by Western blotting, immunostaining, or enzyme-linked immunosorbent assay. RESULTS: Intraperitoneal administration of an anti-HMGB1-neutralizing antibody (AB) at 1 mg/kg prevented the oxaliplatin-induced allodynia in mice and rats. Antagonists of Toll-like receptor (TLR) 4, receptor for advanced glycation end products (RAGE) and CXCR4 among the HMGB1-targeted pro-nociceptive receptors, also mimicked the anti-neuropathic activity of AB in mice. Macrophage accumulation in the sciatic nerve was observed in mice treated with paclitaxel, but not oxaliplatin, and neither macrophage depletion nor inhibitors of macrophage activation affected oxaliplatin-induced allodynia. Oxaliplatin was 10- to 100-fold less potent than paclitaxel in releasing HMGB1 from macrophage-like RAW264.7 cells. Like AB, TMα at 10 mg/kg prevented the oxaliplatin-induced allodynia in mice as well as rats, an effect abolished by argatroban at 10 mg/kg, a thrombin inhibitor. The anti-neuropathic activity of TMα in oxaliplatin-treated mice was suppressed by oral anticoagulants such as warfarin at 1 mg/kg, dabigatran at 75 mg/kg, and rivaroxaban at 10 mg/kg, but not antiplatelet agents such as aspirin at 50 mg/kg and clopidogrel at 10 mg/kg. Repeated administration of the anticoagulants gradually developed neuropathic allodynia and elevated plasma HMGB1 levels in mice treated with a subeffective dose of oxaliplatin. CONCLUSIONS: Our data thus suggests a causative role of HMGB1 derived from non-macrophage cells in oxaliplatin-induced peripheral neuropathy and a thrombin-dependent anti-neuropathic activity of exogenous TMα and, most probably, endogenous TM.
• HMGB1を標的とする化学療法誘発性末梢神経障害の予防

  川畑篤史; 坪田真帆; 関口富美子; 辻田隆一

  日本薬理学雑誌 in press 2019 [Invited]
  
• Prenylflavanones as Novel T-Type Calcium Channel Blockers Useful for Pain Therapy

  SEKIGUCHI FumikoNguyen H-D; Okada T; Sekiguchi F; Tsubota M; Nishikawa H; Kawabata A; Toyooka N

  Nat Prod Commun 2019 1 - 11 2019 [Refereed]
  
• Role of Cav3.2 T-type Ca2+ channels in prostate cancer cells

  Fumiko Sekiguchi; Atsufumi Kawabata

  Nihon Yakurigaku Zasshi 154 (3) 97 - 102 2019 [Invited]
   

  Among voltage-gated Ca2+ channels, T-type Ca2+ channels, which are activated by low voltages, regulate neuronal excitability, spontaneous neurotransmitter release, hormone secretion, etc. and also participate in proliferation of distinct cancer cells. Among three isoforms of T-type Ca2+ channels, Cav3.2 is detectable in 100% of biopsy samples from prostate cancer patients. In general, prostate cancer cells are highly sensitive to androgen deprivation therapy, but often acquire hormone-therapy resistance. The androgen deprivation may trigger neuroendocrine (NE)-like differentiation of some prostate cancer cells. We have analyzed the expression and function of Cav3.2 in human prostate cancer LNCaP cells during NE-like differentiation. NE-like LNCaP cells overexpress Cav3.2 through the CREB/Egr-1 pathway and also cystathionine-γ-lyase (CSE), which generates H2S that enhances the channel activity of Cav3.2. H2S generated by upregulated CSE appears to enhance the activity of upregulated Cav3.2 after the differentiation. The enhanced Cav3.2 activity in NE-like cells may contribute to increased secretion of mitogenic factors essential for androgen-independent proliferation of surrounding prostate cancer cells. It is known that increased extracellular glucose levels enhance Cav3.2 activity through asparagine (N)-linked glycosylation of Cav3.2, which might contribute to diabetic neuropathy. We then found that high glucose accelerates the enhanced channel function and overexpression of Cav3.2 in NE-like LNCaP cells, which might be associated with clinical evidence for diabetes-related poor prognosis of prostate cancer and development of hormone therapy resistance. Thus, Cav3.2 is considered to play a role in the pathophysiology of prostate cancer, and may serve as a therapeutic target.
• [HMGB1 as a target for prevention of chemotherapy-induced peripheral neuropathy].

  Kawabata A; Tsubota M; Sekiguchi F; Tsujita R

  Nihon yakurigaku zasshi. Folia pharmacologica Japonica 154 (5) 236 - 240 0015-5691 2019 [Refereed]
  
• Paclitaxel-induced HMGB1 release from macrophages and its implication for peripheral neuropathy in mice: Evidence for a neuroimmune crosstalk.

  SEKIGUCHI Fumiko; DOMOTO Risa; NAKASHIMA Kana; YAMASOBA Daichi; YAMANISHI Hiroki; TSUBOTA Maho; WAKE Hidenori; NISHIBORI Masahiro; KAWABATA Atsufumi

  Neuropharmacology 141 201 - 213 2018/09 [Refereed]
  
• Blockade of T-type calcium channels by 6-prenylnaringenin, a hop component, alleviates neuropathic and visceral pain in mice.

  Fumiko Sekiguchi; Tomoyo Fujita; Takahiro Deguchi; Sakura Yamaoka; Ken Tomochika; Maho Tsubota; Sumire Ono; Yamato Horaguchi; Maki Ichii; Mio Ichikawa; Yumiko Ueno; Nene Koike; Tadatoshi Tanino; Huy Du Nguyen; Takuya Okada; Hiroyuki Nishikawa; Shigeru Yoshida; Tsuyako Ohkubo; Naoki Toyooka; Kazuya Murata; Hideaki Matsuda; Atsufumi Kawabata

  Neuropharmacology 138 232 - 244 2018/08 [Refereed]
   

  Since Cav3.2 T-type Ca2+ channels (T-channels) expressed in the primary afferents and CNS contribute to intractable pain, we explored T-channel-blocking components in distinct herbal extracts using a whole-cell patch-clamp technique in HEK293 cells stably expressing Cav3.2 or Cav3.1, and purified and identified sophoraflavanone G (SG) as an active compound from SOPHORAE RADIX (SR). Interestingly, hop-derived SG analogues, (2S)-6-prenylnaringenin (6-PNG) and (2S)-8-PNG, but not naringenin, also blocked T-channels; IC50 (μM) of SG, (2S)-6-PNG and (2S)-8-PNG was 0.68-0.75 for Cav3.2 and 0.99-1.41 for Cav3.1. (2S)-6-PNG and (2S)-8-PNG, but not SG, exhibited reversible inhibition. The racemic (2R/S)-6-PNG as well as (2S)-6-PNG potently blocked Cav3.2, but exhibited minor effect on high-voltage-activated Ca2+ channels and voltage-gated Na+ channels in differentiated NG108-15 cells. In mice, the mechanical allodynia following intraplantar (i.pl.) administration of an H2S donor was abolished by oral or i.p. SR extract and by i.pl. SG, (2S)-6-PNG or (2S)-8-PNG, but not naringenin. Intraperitoneal (2R/S)-6-PNG strongly suppressed visceral pain and spinal ERK phosphorylation following intracolonic administration of an H2S donor in mice. (2R/S)-6-PNG, administered i.pl. or i.p., suppressed the neuropathic allodynia induced by partial sciatic nerve ligation or oxaliplatin, an anti-cancer agent, in mice. (2R/S)-6-PNG had little or no effect on open-field behavior, motor performance or cardiovascular function in mice, and on the contractility of isolated rat aorta. (2R/S)-6-PNG, but not SG, was detectable in the brain after their i.p. administration in mice. Our data suggest that 6-PNG, a hop component, blocks T-channels, and alleviates neuropathic and visceral pain with little side effects.
• Design and synthesis of novel anti-hyperalgesic agents based on 6-prenylnaringenin as the T-type calcium channel blockers.

  Du Nguyen Huy; Okada Takuya; Kitamura Shum; Yamaoka Sakura; Horaguchi Yamato; Kasanami Yoshihito; Sekiguchi Fumiko; Tsubota Maho; Yoshida Shigeru; Nishikawa Hiroki; Kawabata Atsufumi; Toyooka Naoki

  Bioorg Med Chem. 19 4410 - 4427 2018/07 [Refereed]
  
• Role of Thrombin in Soluble Thrombomodulin-Induced Suppression of Peripheral HMGB1-Mediated Allodynia in Mice.

  Ryuichi Tsujita; Maho Tsubota; Yusuke Hayashi; Haruka Saeki; Fumiko Sekiguchi; Atsufumi Kawabata

  Journal of neuroimmune pharmacology : the official journal of the Society on NeuroImmune Pharmacology 13 (2) 179 - 188 2018/06 [Refereed]
   

  High mobility group box 1 (HMGB1), a nuclear protein, once released into the extracellular space under pathological conditions, plays a pronociceptive role in redox-dependent distinct active forms, all-thiol HMGB1 (at-HMGB1) and disulfide HMGB1 (ds-HMGB1), that accelerate nociception through the receptor for advanced glycation endproducts (RAGE) and Toll-like receptor 4 (TLR4), respectively. Thrombomodulin (TM), an endothelial membrane protein, and soluble TM, known as TMα, promote thrombin-mediated activation of protein C and also sequester HMGB1, which might facilitate thrombin degradation of HMGB1. The present study aimed at clarifying the role of thrombin in TMα-induced suppression of peripheral HMGB1-dependent allodynia in mice. Thrombin-induced degradation of at-HMGB1 and ds-HMGB1 was accelerated by TMα in vitro. Intraplantar (i.pl.) injection of bovine thymus-derived HMGB1 in an unknown redox state, at-HMGB1, ds-HMGB1 or lipopolysaccharide (LPS), known to cause HMGB1 secretion, produced long-lasting mechanical allodynia in mice, as assessed by von Frey test. TMα, when preadministered i.pl., prevented the allodynia caused by bovine thymus-derived HMGB1, at-HMGB1, ds-HMGB1 or LPS, in a dose-dependent manner. The TMα-induced suppression of the allodynia following i.pl. at-HMGB1, ds-HMGB1 or LPS was abolished by systemic preadministration of argatroban, a thrombin-inhibiting agent, and accelerated by i.pl. co-administered thrombin. Our data clearly indicate that TMα is capable of promoting the thrombin-induced degradation of both at-HMGB1 and ds-HMGB1, and suppresses the allodynia caused by either HMGB1 in a thrombin-dependent manner. Considering the emerging role of HMGB1 in distinct pathological pain models, the present study suggests the therapeutic usefulness of TMα for treatment of intractable and/or persistent pain.
• Involvement of the cystathionine-γ-lyase/Cav3.2 pathway in substance P-induced bladder pain in the mouse, a model for nonulcerative bladder pain syndrome.

  Maho Tsubota; Yasumasa Okawa; Yuhei Irie; Mariko Maeda; Tomoka Ozaki; Fumiko Sekiguchi; Hiroyasu Ishikura; Atsufumi Kawabata

  Neuropharmacology 133 254 - 263 2018/05 [Refereed]
   

  Hydrogen sulfide (H2S) formed by cystathionine-γ-lyase (CSE) enhances the activity of Cav3.2 T-type Ca2+ channels, contributing to the bladder pain accompanying hemorrhagic cystitis caused by systemic administration of cyclophosphamide (CPA) in mice. Given clinical and fundamental evidence for the involvement of the substance P/NK1 receptor systems in bladder pain syndrome (BPS)/interstitial cystitis (IC), we created an intravesical substance P-induced bladder pain model in mice and analyzed the possible involvement of the CSE/Cav3.2 pathway. Bladder pain/cystitis was induced by i.p. CPA or intravesical substance P in female mice. Bladder pain was evaluated by counting nociceptive behavior and by detecting referred hyperalgesia in the lower abdomen and hindpaw. The isolated bladder tissue was weighed to estimate bladder swelling and subjected to histological observation and Western blotting. Intravesical substance P caused profound referred hyperalgesia accompanied by little bladder swelling or edema 6-24 h after the administration, in contrast to i.p. CPA-induced nociceptive behavior/referred hyperalgesia with remarkable bladder swelling/edema and urothelial damage. The bladder pain and/or cystitis symptoms caused by substance P or CPA were prevented by the NK1 receptor antagonist. CSE in the bladder was upregulated by substance P or CPA, and the NK1 antagonist prevented the CPA-induced CSE upregulation. A CSE inhibitor, a T-type Ca2+ channel blocker and gene silencing of Cav3.2 abolished the intravesical substance P-induced referred hyperalgesia. The intravesical substance P-induced pain in mice is useful as a model for nonulcerative BPS, and involves the activation of the NK1 receptor/CSE/H2S/Cav3.2 cascade.
• Involvement of NF-κB in the upregulation of cystathionine-γ-lyase, a hydrogen sulfide-forming enzyme, and bladder pain accompanying cystitis in mice.

  Tomoka Ozaki; Maho Tsubota; Fumiko Sekiguchi; Atsufumi Kawabata

  Clinical and experimental pharmacology & physiology 45 (4) 355 - 361 2018/04 [Refereed]
   

  Hydrogen sulfide (H2 S) is generated from l-cysteine by multiple enzymes including cystathionine-γ-lyase (CSE), and promotes nociception by targeting multiple molecules such as Cav 3.2 T-type Ca2+ channels. Bladder pain accompanying cyclophosphamide (CPA)-induced cystitis in mice has been shown to involve the functional upregulation of the CSE/H2 S/Cav 3.2 pathway. Therefore, we investigated whether NF-κB, as an upstream signal of the CSE/H2 S system, contributes to bladder pain in mice with CPA-induced cystitis. Bladder pain-like nociceptive behaviour was observed in CPA-treated mice, and referred hyperalgesia was evaluated by the von Frey test. Isolated bladder weights were assessed to estimate bladder swelling, and protein levels were measured by Western blotting. CPA, administered intraperitoneally, induced nociceptive behaviour, referred hyperalgesia and increased bladder weights in mice. β-Cyano-l-alanine, a reversible selective CSE inhibitor, prevented CPA-induced nociceptive behaviour, referred hyperalgesia, and, in part, increases in bladder weight. CPA markedly increased phosphorylated NF-κB p65 levels in the bladder, an effect that was prevented by pyrrolidine dithiocarbamate (PDTC), an NF-κB inhibitor. PDTC and curcumin, which inhibits NF-κB signals, abolished CPA-induced nociceptive behaviour, referred hyperalgesia and, in part, increases in bladder weight. CPA caused the overexpression of CSE in the bladder, and this was prevented by PDTC or curcumin. The CPA-induced activation of NF-κB signals appeared to cause CSE overexpression in the bladder, contributing to bladder pain and in part swelling, possibly through H2 S/Cav 3.2 signaling. Therefore, NF-κB-inhibiting compounds including curcumin may be useful for the treatment of cystitis-related bladder pain.
• Zinc deficiency promotes cystitis-related bladder pain by enhancing function and expression of Cav3.2 in mice.

  Tomoka Ozaki; Junki Matsuoka; Maho Tsubota; Shiori Tomita; Fumiko Sekiguchi; Takeshi Minami; Atsufumi Kawabata

  Toxicology 393 102 - 112 2018/01 [Refereed]
   

  Cav3.2 T-type Ca2+ channel activity is suppressed by zinc that binds to the extracellular histidine-191 of Cav3.2, and enhanced by H2S that interacts with zinc. Cav3.2 in nociceptors is upregulated in an activity-dependent manner. The enhanced Cav3.2 activity by H2S formed by the upregulated cystathionine-γ-lyase (CSE) is involved in the cyclophosphamide (CPA)-induced cystitis-related bladder pain in mice. We thus asked if zinc deficiency affects the cystitis-related bladder pain in mice by altering Cav3.2 function and/or expression. Dietary zinc deficiency for 2 weeks greatly decreased zinc concentrations in the plasma but not bladder tissue, and enhanced the bladder pain/referred hyperalgesia (BP/RH) following CPA at 200mg/kg, a subeffective dose, but not 400mg/kg, a maximal dose, an effect abolished by pharmacological blockade or gene silencing of Cav3.2. Acute zinc deficiency caused by systemic N,N,N',N'-tetrakis-(2-pyridylmethyl)-ethylendiamine (TPEN), a zinc chelator, mimicked the dietary zinc deficiency-induced Cav3.2-dependent promotion of BP/RH following CPA at 200mg/kg. CPA at 400mg/kg alone or TPEN plus CPA at 200mg/kg caused Cav3.2 overexpression accompanied by upregulation of Egr-1 and USP5, known to promote transcriptional expression and reduce proteasomal degradation of Cav3.2, respectively, in the dorsal root ganglia (DRG). The CSE inhibitor, β-cyano-l-alanine, prevented the BP/RH and upregulation of Cav3.2, Egr-1 and USP5 in DRG following TPEN plus CPA at 200mg/kg. Together, zinc deficiency promotes bladder pain accompanying CPA-induced cystitis by enhancing function and expression of Cav3.2 in nociceptors, suggesting a novel therapeutic avenue for treatment of bladder pain, such as zinc supplementation.
• Human soluble thrombomodulin-induced blockade of peripheral HMGB1-dependent allodynia in mice requires both the lectin-like and EGF-like domains.

  Yusuke Hayashi; Ryuichi Tsujita; Maho Tsubota; Haruka Saeki; Fumiko Sekiguchi; Goichi Honda; Atsufumi Kawabata

  Biochemical and biophysical research communications 495 (1) 634 - 638 2018/01 [Refereed]
   

  Thrombomodulin (TM), an endothelial protein with anti-coagulant activity, is composed of 5 domains, D1-D5. Recombinant human soluble TM (TMα) consisting of D1-D3, which is generated in CHO cells, suppresses inflammatory and nociceptive signals by inactivating high mobility group box 1 (HMGB1), one of damage-associated molecular patterns. TMα sequesters HMGB1 with the lectin-like D1 and promotes its degradation by thrombin binding to the EGF-like D2. We prepared TM's D123, D1 and D2 by the protein expression system of yeast, and evaluated their effects on HMGB1 degradation in vitro and on the allodynia caused by HMGB1 in distinct redox forms in mice in vivo. TMα and TM's D123, but not D1, promoted the thrombin-dependent degradation of all-thiol (at-HMGB1) and disulfide HMGB1 (ds-HMGB1), an effect mimicked by TM's D2, though to a lesser extent. Intraplantar administration of TMα and TM's D123, but not D1, D2 or D1 plus D2, strongly prevented the mechanical allodynia caused by intraplantar at-HMGB1, ds-HMGB1 or lipopolysaccharide in mice. Our data suggest that, apart from the role of D3, TMα and TM's D123 require both lectin-like D1 capable of sequestering HMGB1 and EGF-like D2 responsible for thrombin-dependent degradation of HMGB1, in abolishing the allodynia caused by exogenous or endogenous HMGB1.
• Prostanoid-dependent bladder pain caused by proteinase-activated receptor-2 activation in mice: Involvement of TRPV1 and T-type Ca2+ channels.

  Maho Tsubota; Tomoka Ozaki; Yuko Hayashi; Yasumasa Okawa; Ayaka Fujimura; Fumiko Sekiguchi; Hiroyuki Nishikawa; Atsufumi Kawabata

  Journal of pharmacological sciences 136 (1) 46 - 49 2018/01 [Refereed]
   

  We studied the pronociceptive role of proteinase-activated receptor-2 (PAR2) in mouse bladder. In female mice, intravesical infusion of the PAR2-activating peptide, SLIGRL-amide (SL), caused delayed mechanical hypersensitivity in the lower abdomen, namely 'referred hyperalgesia', 6-24 h after the administration. The PAR2-triggered referred hyperalgesia was prevented by indomethacin or a selective TRPV1 blocker, and restored by a T-type Ca2+ channel blocker. In human urothelial T24 cells, SL caused delayed prostaglandin E2 production and COX-2 upregulation. Our data suggest that luminal PAR2 stimulation in the bladder causes prostanoid-dependent referred hyperalgesia in mice, which involves the activation of TRPV1 and T-type Ca2+ channels.
• Involvement of Voltage-Gated Calcium Channels in Inflammation and Inflammatory Pain.

  Fumiko Sekiguchi; Maho Tsubota; Atsufumi Kawabata

  Biological & pharmaceutical bulletin 41 (8) 1127 - 1134 2018 [Invited]
   

  Voltage-gated calcium channels (VGCCs) are classified into high-voltage-activated (HVA) channels and low-voltage-activated channels consisting of Cav3.1-3.3, known as T ("transient")-type VGCC. There is evidence that certain types of HVA channels are involved in neurogenic inflammation and inflammatory pain, in agreement with reports indicating the therapeutic effectiveness of gabapentinoids, ligands for the α2δ subunit of HVA, in treating not only neuropathic, but also inflammatory, pain. Among the Cav3 family members, Cav3.2 is abundantly expressed in the primary afferents, regulating both neuronal excitability at the peripheral terminals and spontaneous neurotransmitter release at the spinal terminals. The function and expression of Cav3.2 are modulated by a variety of inflammatory mediators including prostanoids and hydrogen sulfide (H2S), a gasotransmitter. The increased activity of Cav3.2 by H2S participates in colonic, bladder and pancreatic pain, and regulates visceral inflammation. Together, VGCCs are involved in inflammation and inflammatory pain, and Cav3.2 T-type VGCC is especially a promising therapeutic target for the treatment of visceral inflammatory pain in patients with irritable bowel syndrome, interstitial cystitis/bladder pain syndrome, pancreatitis, etc., in addition to neuropathic pain.
• Functional regulation of ion channels by H2S and its pathological impact

  SEKIGUCHI Fumiko; KAWABATA Atsufumi

  硫酸と工業 硫酸協会 70 (5) 61 - 70 0370-8047 2017/05 [Invited]
  
• 6-Prenylnaringenin, a novel T-type Ca2+ channel blocker, enhances neuritogenesis in neural progenitor-like NG108-15 cells via cannabinoid CB1 receptors

  Sekiguchi Fumiko; Noda Sayuri; Ono Sumire; Murata Kazuya; Matsuda Hideaki; Huy Du Nguyen; Toyooka Naoki; Harada Narinobu; Ito Yukari; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 133 (3) S176  1347-8613 2017/03 [Refereed]
  
• Tacrolimus Triggers Transient Receptor Potential Vanilloid-1-Dependent Relapse of Pancreatitis-Related Pain in Mice

  Yuka Terada; Maho Tsubota; Hiiragi Sugo; Kohei Wakitani; Fumiko Sekiguchi; Kyoichi Wada; Mitsutaka Takada; Akira Oita; Atsufumi Kawabata

  PHARMACOLOGY KARGER 99 (5-6) 281 - 285 0031-7012 2017 [Refereed]
   

  Transient receptor potential vanilloid-1 (TRPV1) expressed in nociceptors is directly phosphorylated and activated by protein kinase C, and involved in the signaling of pancreatic pain. On the other hand, Ca(v)3.2 T-type Ca2+ channels expressed in nociceptors are functionally upregulated by phosphorylation with protein kinase A and also play a role in pancreatitis-related pain. Calcineurin, a phosphatase, negatively regulates various channel functions including TRPV1, and calcineurin inhibitor-induced pain syndrome by tacrolimus, a calcineurin inhibitor, used as an immunosuppressant, has been a clinical problem. We thus examined the effect of tacrolimus on pancreatitis-related pain in mice. Repeated treatment with cerulein caused referred hyperalgesia accompanying acute pancreatitis, which was unaffected by tacrolimus. Pancreatitis-related symptoms disappeared in 24 h, whereas the referred hyperalgesia recurred following the administration of tacrolimus, which was abolished by the blockers of TRPV1 but not T-type Ca2+ channels. Thus, tacrolimus appears to cause the TRPV1-dependent relapse of pancreatitis-related pain, suggesting the involvement of calcineurin in the termination of pancreatic pain. (C) 2017 S. Karger AG, Basel
• Repeated Cold Stress Reduces Cyclophosphamide-Induced Cystitis/Bladder Pain and Macrophage Activity in Mice

  Maho Tsubota; Tomoyoshi Miyamoto; Saki Hiruma; Haruka Saeki; Takaya Miyazaki; Fumiko Sekiguchi; Yoshinori Funakami; Atsufumi Kawabata

  PHARMACOLOGY KARGER 99 (5-6) 286 - 290 0031-7012 2017 [Refereed]
   

  We examined the effect of repeated cold (RC) stress on cyclophosphamide (CPA)-induced cystitis/bladder pain in mice, in relation to macrophage activity. CPA, given i.p. at 400 mg/kg, caused bladder pain symptoms accompanying cystitis in both unstressed and RC-stressed mice, which were prevented by the macrophage inhibitor minocycline. A low dose, that is, 200 mg/kg, of CPA still produced bladder pain symptoms in unstressed but not RC-stressed mice. Lipopoly-saccharide-induced cytokine production in peritoneal macrophages from RC-stressed mice was less than that from unstressed mice. Thus, RC stress appears to reduce CPA-induced bladder pain in mice, which may be associated with the decreased macrophage activity. (C) 2017 S. Karger AG, Basel
• Macrophage-derived HMGB1 as a Pain Mediator in the Early Stage of Acute Pancreatitis in Mice: Targeting RAGE and CXCL12/CXCR4 Axis

  Yuhei Irie; Maho Tsubota; Hiroyasu Ishikura; Fumiko Sekiguchi; Yuka Terada; Toshifumi Tsujiuchi; Keyue Liu; Masahiro Nishibori; Atsufumi Kawabata

  JOURNAL OF NEUROIMMUNE PHARMACOLOGY SPRINGER 12 (4) 693 - 707 1557-1890 2017/12 [Refereed]
   

  Extracellular high mobility group box 1 (HMGB1) activates the receptor for advanced glycation end products (RAGE) or Toll-like receptor 4 (TLR4) and forms a heterocomplex with CXCL12 that strongly activates CXCR4, promoting inflammatory and pain signals. In the present study, we investigated the role of HMGB1 in pancreatic pain accompanying cerulein-induced acute pancreatitis in mice. Abdominal referred hyperalgesia accompanying acute pancreatitis occurred within 1 h after 6 hourly injections of cerulein. The anti-HMGB1 neutralizing antibody or recombinant human soluble thrombomodulin (rhsTM), known to inactivate HMGB1, abolished the cerulein-induced referred hyperalgesia, but not pancreatitis itself. Plasma or pancreatic HMGB1 levels did not change, but macrophage infiltration into the pancreas occurred 1 h after cerulein treatment. Minocycline, a macrophage/microglia inhibitor, ethyl pyruvate that inhibits HMGB1 release from macrophages, or liposomal clodronate that depletes macrophages prevented the referred hyperalgesia, but not pancreatitis. Antagonists of RAGE or CXCR4, but not TLR4, strongly suppressed the cerulein-induced referred hyperalgesia, but not pancreatitis. Upregulation of RAGE, CXCR4 and CXCL12, but not TLR4, were detected in the pancreas 1 h after cerulein treatment. Our data suggest that HMGB1 regionally secreted by macrophages mediates pancreatic pain by targeting RAGE and CXCL12/CXCR4 axis in the early stage of acute pancreatitis.
• High glucose induces N-linked glycosylation-mediated functional upregulation and overexpression of Ca(v)3.2 T-type calcium channels in neuroendocrine-like differentiated human prostate cancer cells

  Kazuki Fukami; Erina Asano; Mai Ueda; Fumiko Sekiguchi; Shigeru Yoshida; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 133 (1) 57 - 60 1347-8613 2017/01 [Refereed]
   

  Given that Ca(v)3.2 T-type Ca2+ channels were functionally regulated by asparagine (N)-linked glycosylation, we examined effects of high glucose on the function of Ca(v)3.2, known to regulate secretory function, in neuroendocrine-like differentiated prostate cancer LNCaP cells. High glucose accelerated the increased channel function and overexpression of Ca(v)3.2 during neuroendocrine differentiation, the former prevented by enzymatic inhibition of N-glycosylation and cleavage of N-glycans. Hyperglycemia thus appears to induce N-linked glycosylation-mediated functional upregulation and overexpression of Ca(v)3.2 in neuroendocrine-like differentiated prostate cancer cells. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of Japanese Pharmacological Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
• Hydrogen Sulfide and T-Type Ca2+ Channels in Pain Processing, Neuronal Differentiation and Neuroendocrine Secretion

  Kazuki Fukami; Fumiko Sekiguchi; Atsufumi Kawabata

  PHARMACOLOGY KARGER 99 (3-4) 196 - 203 0031-7012 2017 [Refereed]
   

  Background: Hydrogen sulfide (H2S), a gasotransmitter, is generated from L-cysteine by mainly 3 enzymes, cystathionine-Upsilon-lyase (CSE), cystathionine-beta-synthase, and 3-mercaptopyruvate sulfurtransferase in cooperation with cysteine aminotransferase. The H2S-forming enzymes, particularly CSE, are overexpressed under the pathological conditions such as inflammation, neuronal or neuroendocrine differentiation and cancer development. Given that Ca(v)3.2 T-type Ca2+ channels mediate some of the biological activity of H2S, we focus on the role of the H2S/Ca(v)3.2 pathway in regulating the neuronal and neuroendocrine function. Summary: In the neuronal system, H2S regulates the activity of various ion channels including Ca(v)3.2. Exogenous and endogenous H2S enhances the Ca(v)3.2 channel activity, promoting somatic and visceral pain signaling. The H2S/Ca(v)3.2 pathway also facilitates neuritogenesis or neuronal differentiation. Interestingly, endogenous H2S formed by CSE regulates secretory function by enhancing Ca(v)3.2 channel activity in neuroendocrine-differentiated prostate cancer cells or carotid glomus cells. Key Messages: The H2S/Ca(v)3.2 pathway may serve as therapeutic targets for treatment of intractable pain, neuronal injury, androgen-independent prostate cancer, cardiovascular diseases, etc. (C) 2016 S. Karger AG, Basel
• Therapeutic potential of RQ-00311651, a novel T-type Ca2+ channel blocker, in distinct rodent models for neuropathic and visceral pain

  Fumiko Sekiguchi; Yuma Kawara; Maho Tsubota; Eri Kawakami; Tomoka Ozaki; Yudai Kawaishi; Shiori Tomita; Daiki Kanaoka; Shigeru Yoshida; Tsuyako Ohkubo; Atsufumi Kawabata

  PAIN LIPPINCOTT WILLIAMS & WILKINS 157 (8) 1655 - 1665 0304-3959 2016/08 [Refereed]
   

  T-type Ca2+ channels (T channels), particularly Ca(v)3.2 among the 3 isoforms, play a role in neuropathic and visceral pain. We thus characterized the effects of RQ-00311651 (RQ), a novel T-channel blocker, in HEK293 cells transfected with human Ca(v)3.1 or Ca(v)3.2 by electrophysiological and fluorescent Ca2+ signaling assays, and also evaluated the antiallodynic/antihyperalgesic activity of RQ in somatic, visceral, and neuropathic pain models in rodents. RQ-00311651 strongly suppressed T currents when tested at holding potentials of -65 similar to - 260 mV, but not -80 mV, in the Ca(v)3.1- or Ca(v)3.2-expressing cells. RQ-00311651 also inhibited high K+-induced Ca2+ signaling in those cells. In mice, RQ, administered intraperitoneally (i.p.) at 5 to 20 mg/kg or orally at 20 to 40 mg/kg, significantly suppressed the somatic hyperalgesia and visceral pain-like nociceptive behavior/referred hyperalgesia caused by intraplantar and intracolonic administration of NaHS or Na2S, H2S donors, respectively, which involve the enhanced activity of Ca(v)3.2 channels. RQ-00311651, given i.p. at 5 to 20 mg/kg, exhibited antiallodynic or antihyperalgesic activity in rats with spinal nerve injury-induced neuropathy or in rats and mice with paclitaxel-induced neuropathy. Oral and i.p. RQ at 10 to 20 mg/kg also suppressed the visceral nociceptive behavior and/or referred hyperalgesia accompanying cerulein-induced acute pancreatitis and cyclophosphamide-induced cystitis in mice. The analgesic and antihyperalgesic/antiallodynic doses of oral and i.p. RQ did not significantly affect the locomotor activity and motor coordination. Together, RQ is considered a state-dependent blocker of Ca(v)3.1/Ca(v)3.2 T channels and may serve as an orally available analgesic for treatment of neuropathic and inflammatory pain including distinct visceral pain with minimum central side effects.
• Involvement of high mobility group box 1 in the development and maintenance of chemotherapy-induced peripheral neuropathy in rats

  Takeshi Nishida; Maho Tsubota; Yudai Kawaishi; Hiroki Yamanishi; Natsuki Kamitani; Fumiko Sekiguchi; Hiroyasu Ishikura; Keyue Liu; Masahiro Nishibori; Atsufumi Kawabata

  TOXICOLOGY ELSEVIER IRELAND LTD 365 48 - 58 0300-483X 2016/07 [Refereed]
   

  Given that high mobility group box 1 (HMGB1), a nuclear protein, once released to the extracellular space, promotes nociception, we asked if inactivation of HMGB1 prevents or reverses chemotherapy-induced painful neuropathy in rats and also examined possible involvement of Toll-like receptor 4 (TLR4) and the receptor for advanced glycation endproduct (RAGE), known as targets for HMGB1. Painful neuropathy was produced by repeated i.p. administration of paclitaxel or vincristine in rats. Nociceptive threshold was determined by the paw pressure method and/or von Frey test in the hindpaw. Tissue protein levels were determined by immunoblotting. Repeated i.p. administration of the anti-HMGB1-neutralizing antibody or recombinant human soluble thrombomodulin (rhsTM), known to inactivate HMGB1, prevented the development of hyperalgesia and/or allodynia induced by paclitaxel or vincristine in rats. A single i.p. or intraplantar (i.pl.) administration of the antibody or rhsTM reversed the chemotherapy induced neuropathy. A single i.pl. administration of a TLR4 antagonist or low molecular weight heparin, known to inhibit RAGE, attenuated the hyperalgesia caused by i.pl. HMGB1 and also the chemotherapy induced painful neuropathy. Paclitaxel or vincristine treatment significantly decreased protein levels of HMGB1 in the dorsal root ganglia, but not sciatic nerves. HMGB1 thus participates in both development and maintenance of chemotherapy-induced painful neuropathy, in part through RAGE and TLR4. HMGB1 inactivation is considered useful to prevent and treat the chemotherapy-induced painful neuropathy. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
• Endogenous Hydrogen Sulfide Enhances Cell Proliferation of Human Gastric Cancer AGS Cells

  Fumiko Sekiguchi; Teruki Sekimoto; Ayaka Ogura; Atsufumi Kawabata

  BIOLOGICAL & PHARMACEUTICAL BULLETIN PHARMACEUTICAL SOC JAPAN 39 (5) 887 - 890 0918-6158 2016/05 [Refereed]
   

  Hydrogen sulfide (H2S), the third gasotransmitter, is endogenously generated by certain H2S synthesizing enzymes, including cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthase (CBS) from L-cysteine in the mammalian body. Several studies have shown that endogenous and exogenous H2S affects the proliferation of cancer cells, although the effects of H2S appear to vary with cell type, being either promotive or suppressive. In the present study, we determined whether endogenously formed H2S regulates proliferation in human gastric cancer AGS cells. CSE, but not CBS, was expressed in AGS cells. CSE inhibitors, DL-propargylglycine (PPG) and beta-cyano-L-alanine (BCA), significantly suppressed the proliferation of AGS cells in a concentration-dependent manner. CSE inhibitors did not increase lactate dehydrogenase (LDH) release in the same concentration range. The inhibitory effects of PPG and BCA on cell proliferation were reversed by repetitive application of NaHS, a donor of H2S. Interestingly, nuclear condensation and fragmentation were detected in AGS cells treated with PPG or BCA. These results suggest that endogenous H2S produced by CSE may contribute to the proliferation of gastric cancer AGS cells, most probably through anti-apoptotic actions.
• Pharmacological characterization of sophoraflavanone G and 6-prenylnaringenin, novel T-type Ca2+ channel blockers: distinct electrophysiological properties and anti-hyperalgesic activity in mice

  Ono Sumire; Yamaoka Sakura; Sekiguchi Fumiko; Ichii Maki; Fujita Tomoyo; Deguchi Takahiro; Tsubota Maho; Nishikawa Hiroyuki; Yoshida Shigeru; Murata Kazuya; Matsuda Hideaki; Toyooka Naoki; Ohkubo Tsuyako; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 130 (3) S146 - S146 1347-8613 2016/03 [Refereed]
  
• The hyperalgesia induced by peripheral HMGB1 in distinct redox states involves different mechanisms

  Tsubota Maho; Yamasoba Daichi; Domoto Risa; Sekiguchi Fumiko; Nishibori Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 130 (3) S235 - S235 1347-8613 2016/03 [Refereed]
  
• The prostaglandin E-2/EP4 receptor/cyclic AMP/T-type Ca2+ channel pathway mediates neuritogenesis in sensory neuron-like ND7/23 cells

  Kenji Mitani; Fumiko Sekiguchi; Takashi Maeda; Yukari Tanaka; Shigeru Yoshida; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 130 (3) 177 - 180 1347-8613 2016/03 [Refereed]
   

  We investigated mechanisms for the neuritogenesis caused by prostaglandin E-2 (PGE(2)) or intracellular cyclic AMP (cAMP) in sensory neuron-like ND7/23 cells. PGE(2) caused neuritogenesis, an effect abolished by an EP4 receptor antagonist or inhibitors of adenylyl cyclase (AC) or protein kinase A (PKA) and mimicked by the AC activator forskolin, dibutyryl cAMP (db-cAMP), and selective activators of PKA or Epac. ND7/23 cells expressed both Ca(v)3.1 and Ca(v)3.2 T-type Ca2+ channels (T-channels). The neuritogenesis induced by db-cAMP or PGE(2) was abolished by T-channel blockers. T-channels were functionally upregulated by db-cAMP. The PGE(2)/EP4/cAMP/T-channel pathway thus appears to mediate neuritogenesis in sensory neurons. (C) 2016 Japanese Pharmacological Society. Production and hosting by Elsevier B.V.
• Peripheral HMGB1-induced hyperalgesia in mice: Redox state-dependent distinct roles of RAGE and TLR4

  Daichi Yamasoba; Maho Tsubota; Risa Domoto; Fumiko Sekiguchi; Hiroyuki Nishikawa; Keyue Liu; Masahiro Nishibori; Hiroyasu Ishikura; Tetsushi Yamamoto; Atsushi Taga; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 130 (2) 139 - 142 1347-8613 2016/02 [Refereed]
   

  Nuclear HMGB1 that contains 3 cysteine residues is acetylated and secreted to the extracellular space, promoting inflammation via multiple molecules such as RAGE and TLR4. We thus evaluated and characterized the redox state-dependent effects of peripheral HMGB1 on nociception. Intraplantar (i.pl.) administration of bovine thymus-derived HMGB1 (bt-HMGB1), all-thiol HMGB1 (at-HMGB1) or disulfide HMGB1 (ds-HMGB1) caused long-lasting mechanical hyperalgesia in mice. The hyperalgesia following i.pl. bt-HMGB1 or at-HMGB1 was attenuated by RAGE inhibitors, while the ds-HMGB1-induced hyperalgesia was abolished by a TLR4 antagonist. Thus, nociceptive processing by peripheral HMGB1 is considered dependent on its redox states. (C) 2016 Japanese Pharmacological Society. Production and hosting by Elsevier B.V.
• Selective sensitization of C-fiber nociceptors by hydrogen sulfide

  Yuka Aoki; Maho Tsubota; Yuta Nishimoto; Yumi Maeda; Fumiko Sekiguchi; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 130 (1) 38 - 41 1347-8613 2016/01 [Refereed]
   

  We examined the effects of intraplantar (i.pl.) administration of NaHS, an H2S donor, known to cause T-type Ca2+ channel (T-channel)-dependent mechanical hyperalgesia, on responsiveness to electric stimulation with 5, 250 and 2000 Hz sine waves (SW) that selectively excites C, A delta and A beta fibers, respectively. NaHS, given i.pl., caused behavioral hypersensitivity to SW stimulation at 5 Hz, but not 250 or 2000 Hz, in rats. NaHS also enhanced phosphorylation of spinal ERK following 5 Hz SW stimulation. Three distinct T-channel blockers abolished the NaHS-induced behavioral hypersensitivity to 5 Hz SW stimulation. Thus, H2S selectively sensitizes C-fiber nociceptors via T-channels. (C) 2016 Japanese Pharmacological Society. Production and hosting by Elsevier B.V.
• Functional upregulation of the H2S/Ca(v)3.2 channel pathway accelerates secretory function in neuroendocrine-differentiated human prostate cancer cells

  Kazuki Fukami; Fumiko Sekiguchi; Miku Yasukawa; Erina Asano; Ryuji Kasamatsu; Mai Ueda; Shigeru Yoshida; Atsufumi Kawabata

  BIOCHEMICAL PHARMACOLOGY PERGAMON-ELSEVIER SCIENCE LTD 97 (3) 300 - 309 0006-2952 2015/10 [Refereed]
   

  Neuroendocrine-differentiated prostate cancer cells may contribute to androgen-independent proliferation of surrounding cells through Ca2+-dependent secretion of mitogenic factors. Human prostate cancer LNCaP cells, when neuroendocrine-differentiated, overexpress Ca(v)3.2 T-type Ca2+ channels that contribute to Ca2+-dependent secretion. Given evidence for the acceleration of Ca(v)3.2 activity by hydrogen sulfide (H2S), we examined the roles of the H2S/Ca(v)3.2 pathway and then analyzed the molecular mechanisms of the Ca(v)3.2 overexpression in neuroendocrine-differentiated LNCaP cells. LNCaP cells were differentiated by dibutyryl cyclic AMP. Protein levels and T-type Ca2+ channeldependent currents (T-currents) were measured by immunoblotting and whole-cell pacth-clamp technique, respectively. Spontaneous release of prostatic acid phosphatase (PAP) was monitored to evaluate secretory function. The differentiated LNCaP cells exhibited neurite outgrowth, androgenindependent proliferation and upregulation of mitogenic factors, and also showed elevation of Ca(v)3.2 expression or T-currents. Expression of cystathionine-gamma-Iyase (CSE) and cystathionine-beta-synthase (CBS), H2S-forming enzymes, and spontaneous secretion of PAP increased following the differentiation. The augmented T-currents were enhanced by H2S donors and suppressed by inhibitors of CSE, but not CBS. The PAP secretion was reduced by inhibition of CSE or T-type Ca2+ channels. During differentiation, Egr-1 and REST, positive and negative transcriptional regulators for Ca(v)3.2, were upregulated and downregulated, respectively, and Egr-1 knockdown prevented the Ca(v)3.2 overexpression. Our data suggest that, in neuroendocrine-differentiated LNCaP cells, H2S formed by the upregulated CSE promotes the activity of the upregulated Ca(v)3.2, leading to the elevated secretory functions. The overexpression of Ca(v)3.2 appears to involve upregulation of Egr-1 and downregulation of REST. (C) 2015 Elsevier Inc. All rights reserved.
• Macrophage-derived HMGB1 contributes to the inflammatory hyperalgegia through the NF-kappa B pathway

  Yamasoba Daichi; Seki Yukari; Yamanishi Hiroki; Tsubota Maho; Sekiguchi Fumiko; Yagi Hideki; Masuko Takashi; Nishibori Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 128 (3) S104 - S104 1347-8613 2015/07 [Refereed]
  
• Roles of Ca(v)3.2 and TRPA1 Channels Targeted by Hydrogen Sulfide in Pancreatic Nociceptive Processing in Mice With or Without Acute Pancreatitis

  Yuka Terada; Mayuko Fujimura; Sachiyo Nishimura; Maho Tsubota; Fumiko Sekiguchi; Atsufumi Kawabata

  JOURNAL OF NEUROSCIENCE RESEARCH WILEY-BLACKWELL 93 (2) 361 - 369 0360-4012 2015/02 [Refereed]
   

  Hydrogen sulfide (H2S), formed by multiple enzymes, including cystathionine--lyase (CSE), targets Ca(v)3.2 T-type Ca2+ channels (T channels) and transient receptor potential ankyrin-1 (TRPA1), facilitating somatic pain. Pancreatitis-related pain also appears to involve activation of T channels by H2S formed by the upregulated CSE. Therefore, this study investigates the roles of the Ca(v)3.2 isoform and/or TRPA1 in pancreatic nociception in the absence and presence of pancreatitis. In anesthetized mice, AP18, a TRPA1 inhibitor, abolished the Fos expression in the spinal dorsal horn caused by injection of a TRPA1 agonist into the pancreatic duct. As did mibefradil, a T-channel inhibitor, in our previous report, AP18 prevented the Fos expression following ductal NaHS, an H2S donor. In the mice with cerulein-induced acute pancreatitis, the referred hyperalgesia was suppressed by NNC 55-0396 (NNC), a selective T-channel inhibitor; zinc chloride; or ascorbic acid, known to inhibit Ca(v)3.2 selectively among three T-channel isoforms; and knockdown of Ca(v)3.2. In contrast, AP18 and knockdown of TRPA1 had no significant effect on the cerulein-induced referred hyperalgesia, although they significantly potentiated the antihyperalgesic effect of NNC at a subeffective dose. TRPA1 but not Ca(v)3.2 in the dorsal root ganglia was downregulated at a protein level in mice with cerulein-induced pancreatitis. The data indicate that TRPA1 and Ca(v)3.2 mediate the exogenous H2S-induced pancreatic nociception in naive mice and suggest that, in the mice with pancreatitis, Ca(v)3.2 targeted by H2S primarily participates in the pancreatic pain, whereas TRPA1 is downregulated and plays a secondary role in pancreatic nociceptive signaling. (c) 2014 Wiley Periodicals, Inc.
• Polaprezinc attenuates cyclophosphamide-induced cystitis and related bladder pain in mice

  Masahiro Murakami-Nakayama; Maho Tsubota; Saki Hiruma; Fumiko Sekiguchi; Kenji Matsuyama; Takeshi Kimura; Masahiro Moriyama; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 127 (2) 223 - 228 1347-8613 2015/02 [Refereed]
   

  Ca(v)3.2 T-type Ca2+ channels targeted by H2S, a gasotransmitter, participate in cyclophosphamide-induced cystitis and bladder pain. Given that zinc selectively inhibits Ca(v)3.2 among T-channel isoforms and also exhibits antioxidant activity, we examined whether polaprezinc (zinc-L-carnosine), a medicine for peptic ulcer treatment and zinc supplementation, reveals preventive or therapeutic effects on bladder inflammation and/or pain in the mouse with cyclophosphamide-induced cystitis, a model for interstitial cystitis. Systemic administration of cyclophosphamide caused cystitis-related symptoms including increased bladder weight and vascular permeability, and histological signs of bladder edema, accompanied by bladder pain-like nociceptive behavior/referred hyperalgesia. All these symptoms were significantly attenuated by oral preadministration of polaprezinc at 400 mg/kg. The same dose of polaprezinc also prevented the increased malondialdehyde level, an indicator of lipid peroxidation, and protein upregulation of cystathionine-gamma-Iyase. an H2S-generating enzyme, but not occludin, a tight junction-related membrane protein, in the bladder tissue of cyclophosphamide-treated mice. Oral posttreatment with polaprezinc at 30-100 mg/kg reversed the nociceptive behavior/referred hyperalgesia in a dose-dependent manner without affecting the increased bladder weight. Together, our data show that zinc supplementation with polaprezinc prevents the cyclophosphamide-induced cystitis probably through the antioxidant activity, and, like T-channel blockers, reverses the established cystitis-related bladder pain in mice, suggesting novel therapeutic usefulness of polaprezinc. (C) 2015 Japanese Pharmacological Society. Production and hosting by Elsevier B.V. All rights reserved.
• Mechanisms for proteinase-activated receptor 1-triggered prostaglandin E-2 generation in mouse osteoblastic MC3T3-E1 cells

  Yuma Maeda; Fumiko Sekiguchi; Rumi Yamanaka; Ryo Sugimoto; Daichi Yamasoba; Shiori Tomita; Hiroyuki Nishikawa; Atsufumi Kawabata

  BIOLOGICAL CHEMISTRY WALTER DE GRUYTER GMBH 396 (2) 153 - 162 1431-6730 2015/02 [Refereed]
   

  We analyzed signaling mechanisms for prostaglandin E-2 (PGE(2)) production following activation of proteinase-activated receptor-1 (PAR1), a thrombin receptor, in preosteoblastic MC3T3-E1 cells. PAR1 stimulation caused PGE(2) release, an effect suppressed by inhibitors ;of COX-1, COX-2, iPLA(2), cPLA(2), MAP kinases (MAPKs), Src, EGF receptor (EGFR) tyrosine kinase (EGFR-TK) and matrix metalloproteinase (MMP), but not by an intracellular Ca2+ chelator or inhibitors of PI3 kinase, protein kinase C (PKC) and NF-kappa B. PAR1 activation induced phosphorylation of MAPKs and upregulation of COX-2. The phosphorylation of p38 MAPK was suppressed by inhibitors of Src and EGFR-TK. The COX-2 upregulation was dependent on ERK, p38, EGFR-TK, Src, and COX-2 itself. PAR1 activation also induced MEK-dependent phosphorylation of cAMP response element binding protein (CREB). All inhibitors of EP1, EP2, EP3 and EP4 receptors suppressed the PAR1-triggered PGE(2) release. Exogenously applied PGE(2) facilitated PAR1-triggered COX-2 upregulation, but it alone had no effect. Together, the PAR1-mediated PGE(2) production in MC3T3-E1 cells appears to involve iPLA(2) and cPLA(2) for arachidonic acid release, and the MEK/ERK/CREB and Src/MMP/EGFR/p38 pathways for COX-2 upregulation, which is facilitated by endogenous PGE(2) formed by COX-2. These signaling mechanisms might underlie the role of the thrombin/PAR1/PGE(2) system in the early stage of the bone healing.
• Bladder pain relief by HMGB1 neutralization and soluble thrombomodulin in mice with cyclophosphamide-induced cystitis

  Junichi Tanaka; Kaoru Yamaguchi; Hiroyasu Ishikura; Maho Tsubota; Fumiko Sekiguchi; Yukari Seki; Toshifumi Tsujiuchi; Akira Murai; Takehiro Umemura; Atsufumi Kawabata

  NEUROPHARMACOLOGY PERGAMON-ELSEVIER SCIENCE LTD 79 112 - 118 0028-3908 2014/04 [Refereed]
   

  High mobility group box 1 (HMGB1), one of damage-associated molecular patterns (DAMPs), plays roles in not only inflammation but also processing of somatic pain. Given that no evidence for roles of HMGB1 in visceral pain signaling is available, we asked if HMGB1 participates in bladder pain accompanying cystitis caused by cyclophosphamide in mice, using the anti-HMGB1 neutralizing antibody and recombinant human soluble thrombomodulin (rhsTM) that sequesters HMGB1 and promotes its degradation by thrombin. Cyclophosphamide, administered i.p., caused bladder pain-like nociceptive behavior and referred hyperalgesia accompanying cystitis symptoms including increased bladder weight, an indicator of edema, in mice. The cyclophosphamide-induced bladder pain and referred hyperalgesia, but not increased bladder weight, were prevented by i.p. preadministration of the anti-HMGB1 neutralizing antibody or rhsTM. HMGB1, given i.p., facilitated the bladder pain and referred hyperalgesia caused by a subeffective dose of cyclophosphamide, an effect blocked by rhsTM. In the cyclophosphamide-treated mice, HMGB1 levels greatly decreased in the bladder tissue, particularly in the urothelial cells, but did not change in the plasma. Low molecular weight heparin, known to inhibit the receptor for advanced glycation end products (RAGE), but not lipopolysaccharide from Rhodobacter sphaeroides, an inhibitor of toll-like receptor 4 (TLR4), blocked the cyclophosphamide-induced bladder pain and referred hyperalgesia. Thus, our data indicate involvement of HMGB1 in the cyclophosphamide-induced bladder pain signaling, but not cystitis itself, and suggest that targeting HMGB1 with rhsTM or blocking RAGE might serve as a novel therapeutic strategy for the management of bladder pain. (C) 2013 Elsevier Ltd. All rights reserved.
• Endogenous and exogenous hydrogen sulfide facilitates T-type calcium channel currents in Ca(v)3.2-expressing HEK293 cells

  Fumiko Sekiguchi; Yosuke Miyamoto; Daiki Kanaoka; Hiroki Ide; Shigeru Yoshida; Tsuyako Ohkubo; Atsufumi Kawabata

  BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS ACADEMIC PRESS INC ELSEVIER SCIENCE 445 (1) 225 - 229 0006-291X 2014/02 [Refereed]
   

  Hydrogen sulfide (H2S), a gasotransmitter, is formed from L-cysteine by multiple enzymes including cystathionine-gamma-lyase (CSE). We have shown that an H2S donor, NaHS, causes hyperalgesia in rodents, an effect inhibited by knockdown of Ca(v)3.2 T-type Ca2+ channels (T-channels), and that NaHS facilitates T-channel-dependent currents (T-currents) in NG108-15 cells that naturally express Ca(v)3.2. In the present study, we asked if endogenous and exogenous H2S participates in regulation of the channel functions in Ca(v)3.2-transfected HEK293 (Ca(v)3.2-HEK293) cells. DL-Propargylglycine (PPG), a CSE inhibitor, significantly decreased T-currents in Ca(v)3.2-HEK293 cells, but not in NG108-15 cells. NaHS at 1.5 mM did not affect T-currents in Ca(v)3.2-HEK293 cells, but enhanced T-currents in NG108-15 cells. In the presence of PPG, NaHS at 1.5 mM, but not 0.1-0.3 mM, increased T-currents in Ca(v)3.2-HEK293 cells. Similarly, Na2S, another H2S donor, at 0.1-0.3 mM significantly increased T-currents in the presence, but not absence, of PPG in Ca(v)3.2-HEK293 cells. Expression of CSE was detected at protein and mRNA levels in HEK293 cells. Intraplantar administration of Na2S, like NaHS, caused mechanical hyperalgesia, an effect blocked by NNC 55-0396, a T-channel inhibitor. The in vivo potency of Na2S was higher than NaHS. These results suggest that the function of Ca(v)3.2 T-channels is tonically enhanced by endogenous H2S synthesized by CSE in Ca(v)3.2-HEK293 cells, and that exogenous H2S is capable of enhancing Ca(v)3.2 function when endogenous H2S production by CSE is inhibited. In addition, Na2S is considered a more potent H2S donor than NaHS in vitro as well as in vivo. (C) 2014 Elsevier Inc. All rights reserved.
• 苦参由来T型Ca2+チャネル阻害物質の検索 ヒトCav3.2発現HEK293細胞における電気生理学的検討とマウスにおける硫化水素誘起痛覚過敏に対する抑制効果の評価

  藤田 友代; 関口 富美子; 出口 貴浩; 吉田 繁; 村田 和也; 松田 秀秋; 大久保 つや子; 川畑 篤史

  日本薬理学雑誌 (公社)日本薬理学会 142 (5) 10P - 10P 0015-5691 2013/11
• Contribution of TRPA1 as a Downstream Signal of Proteinase-Activated Receptor-2 to Pancreatic Pain

  Yuka Terada; Mayuko Fujimura; Sachiyo Nishimura; Maho Tsubota; Fumiko Sekiguchi; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 123 (3) 284 - 287 1347-8613 2013/11 [Refereed]
   

  We examined if TRPA1, like TRPV1, contributes to pancreatic nociceptor excitation following proteinase-activated receptor-2 (PAR2) stimulation and to pancreatitis-related pain in mice. A PAR2-activating peptide, infused into the pancreatic duct, caused spinal Fos expression, which was prevented by AP18, a TRPA1 inhibitor. Repeated administration of cerulein caused referred hyperalgesia accompanying pancreatitis, which was reversed by SB366791, a TRPV1 inhibitor, but not AP18. AP18, administered in combination with a subeffective dose of SB366791, significantly suppressed the referred hyperalgesia. Our findings suggest that TRPA1, like TRPV1, mediates PAR2-triggered pancreatic nociception and that TRPA1 in collaboration with TRPV1 latently contributes to pancreatitis-related pain.
• Recombinant human soluble thrombomodulin prevents peripheral HMGB1-dependent hyperalgesia in rats

  Junichi Tanaka; Yukari Seki; Hiroyasu Ishikura; Maho Tsubota; Fumiko Sekiguchi; Kaoru Yamaguchi; Akira Murai; Takehiro Umemura; Atsufumi Kawabata

  British Journal of Pharmacology 170 (6) 1233 - 1241 0007-1188 2013/11 [Refereed]
   

  Background and Purpose High-mobility group box 1 (HMGB1), a nuclear protein, is actively or passively released during inflammation. Recombinant human soluble thrombomodulin (rhsTM), a medicine for treatment of disseminated intravascular coagulation (DIC), sequesters HMGB1 and promotes its degradation. Given evidence for involvement of HMGB1 in pain signalling, we determined if peripheral HMGB1 causes hyperalgesia, and then asked if rhsTM modulates the HMGB1-dependent hyperalgesia. Experimental Approach Mechanical nociceptive threshold and swelling in rat hindpaw were determined by the paw pressure test and by measuring paw thickness, respectively, and HMGB1 levels in rat hindpaw plantar tissue, dorsal root ganglion (DRG) and serum were determined by Western blotting or elisa. Key Results Intraplantar (i.pl.) administration of HMGB1 rapidly evoked paw swelling and gradually caused hyperalgesia in rats. Systemic administration of rhsTM abolished HMGB1-induced hyperalgesia, and partially blocked paw swelling. LPS, administered i.pl., rapidly produced mild paw swelling, and gradually caused hyperalgesia. The anti-HMGB1 neutralizing antibody abolished LPS-induced hyperalgesia, but partially inhibited paw swelling. rhsTM at a high dose, 10 mg kg-1, prevented both hyperalgesia and paw swelling caused by LPS. In contrast, rhsTM at low doses, 0.001-1 mg kg-1, abolished the LPS-induced hyperalgesia, but not paw swelling. HMGB1 levels greatly decreased in the hindpaw, but not DRG. Serum HMGB1 tended to increase after i.pl. LPS in rats pretreated with vehicle, but not rhsTM. Conclusion and Implications These data suggest that peripheral HMGB1 causes hyperalgesia, and that rhsTM abolishes HMGB1-dependent hyperalgesia, providing novel evidence for therapeutic usefulness of rhsTM as an analgesic. © 2013 The British Pharmacological Society.
• T-type Calcium Channels: Functional Regulation and Implication in Pain Signaling

  Fumiko Sekiguchi; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 122 (4) 244 - 250 1347-8613 2013/08 [Refereed][Invited]
   

  Low-voltage-activated T-type Ca2+ channels (T-channels), especially Ca(v)3.2 among the three isoforms (Ca(v)3.1, Ca(v)3.2, and Ca(v)3.3), are now considered to play pivotal roles in processing of pain signals. Ca(v)3.2 T-channels are functionally modulated by extracellular substances such as hydrogen sulfide and ascorbic acid, by intracellular signaling molecules including protein kinases, and by glycosylation. Ca(v)3.2 T-channels are abundantly expressed in both peripheral and central endings of the primary afferent neurons, regulating neuronal excitability and release of excitatory neurotransmitters such as substance P and glutamate, respectively. Functional upregulation of Ca(v)3.2 T-channels is involved in the pathophysiology of inflammatory, neuropathic, and visceral pain. Thus, Ca(v)3.2 T-channels are considered to serve as novel targets for development of drugs for treatment of intractable pain resistant to currently available analgesics.
• Inhibition by Hydrogen Sulfide of Rabbit Platelet Aggregation and Calcium Mobilization

  Hiroyuki Nishikawa; Hitomi Hayashi; Satoko Kubo; Maho Tsubota-Matsunami; Fumiko Sekiguchi; Atsufumi Kawabata

  BIOLOGICAL & PHARMACEUTICAL BULLETIN PHARMACEUTICAL SOC JAPAN 36 (8) 1278 - 1282 0918-6158 2013/08 [Refereed]
   

  Hydrogen sulfide (H2S), a gasotransmitter, plays a variety of roles in the mammalian body including the cardiovascular system. Given evidence that H2S donors including NaHS inhibit human platelet aggregation, we examined and characterized the effects of NaFIS on rabbit platelet aggregation and cytosolic Ca2+ mobilization. Rabbit platelet aggregation was determined in platelet-rich plasma (PRP) and washed platelets. Intracellular Ca2+ levels were monitored in Fura2-loaded washed platelets. NaHS prevented rabbit platelet aggregation induced by collagen or ADP, and the effective concentration range of NaHS was 0.1-0.3 mM in PRP and 1-3 mM in washed platelets. In washed platelets, NaHS attenuated cytosolic Ca2+ mobilization induced by collagen or ADP and also reduced platelet aggregation induced by ionomycin, a Ca2+ ionophore. The antiplatelet effect of NaHS was blocked by an adenylyl cyclase inhibitor and enhanced by a phosphodiesterase inhibitor. H2S thus suppresses rabbit platelet aggregation by interfering with both upstream and downstream signals of cytosolic Ca2+ mobilization in a cAMP-dependent manner.
• AKAP-dependent sensitization of Cav3.2 channels via the EP4 receptor/cAMP pathway mediates PGE2-induced mechanical hyperalgesia

  Fumiko Sekiguchi; Yuka Aoki; Maiko Nakagawa; Daiki Kanaoka; Yuta Nishimoto; Maho Tsubota-Matsunami; Rumi Yamanaka; Shigeru Yoshida; Atsufumi Kawabata

  BRITISH JOURNAL OF PHARMACOLOGY WILEY-BLACKWELL 168 (3) 734 - 745 0007-1188 2013/02 

  Background and Purpose The Cav3.2 isoform of T-type Ca2+ channels (T channels) is sensitized by hydrogen sulfide, a pro-nociceptive gasotransmitter, and also by PKA that mediates PGE2-induced hyperalgesia. Here we examined and analysed Cav3.2 sensitization via the PGE2/cAMP pathway in NG108-15 cells that express Cav3.2 and produce cAMP in response to PGE2, and its impact on mechanical nociceptive processing in rats. Experimental Approach In NG108-15 cells and rat dorsal root ganglion (DRG) neurons, T-channel-dependent currents (T currents) were measured with the whole-cell patch-clamp technique. The molecular interaction of Cav3.2 with A-kinase anchoring protein 150 (AKAP150) and its phosphorylation were analysed by immunoprecipitation/immunoblotting in NG108-15 cells. Mechanical nociceptive threshold was determined by the paw pressure test in rats. Key Results In NG108-15 cells and/or rat DRG neurons, dibutyryl cAMP (db-cAMP) or PGE2 increased T currents, an effect blocked by AKAP St-Ht31 inhibitor peptide (AKAPI) or KT5720, a PKA inhibitor. The effect of PGE2 was abolished by RQ-00015986-00, an EP4 receptor antagonist. AKAP150 was co-immunoprecipitated with Cav3.2, regardless of stimulation with db-cAMP, and Cav3.2 was phosphorylated by db-cAMP or PGE2. In rats, intraplantar (i.pl.) administration of db-cAMP or PGE2 caused mechanical hyperalgesia, an effect suppressed by AKAPI, two distinct T-channel blockers, NNC 55-0396 and ethosuximide, or ZnCl2, known to inhibit Cav3.2 among T channels. Oral administration of RQ-00015986-00 suppressed the PGE2-induced mechanical hyperalgesia. Conclusion and Implications Our findings suggest that PGE2 causes AKAP-dependent phosphorylation and sensitization of Cav3.2 through the EP4 receptor/cAMP/PKA pathway, leading to mechanical hyperalgesia in rats.
• AKAP-dependent sensitization of Cav3.2 channels via the EP4 receptor/cAMP pathway mediates PGE2-induced mechanical hyperalgesia

  Fumiko Sekiguchi; Yuka Aoki; Maiko Nakagawa; Daiki Kanaoka; Yuta Nishimoto; Maho Tsubota-Matsunami; Rumi Yamanaka; Shigeru Yoshida; Atsufumi Kawabata

  BRITISH JOURNAL OF PHARMACOLOGY WILEY-BLACKWELL 168 (3) 734 - 745 0007-1188 2013/02 [Refereed]
   

  Background and Purpose The Cav3.2 isoform of T-type Ca2+ channels (T channels) is sensitized by hydrogen sulfide, a pro-nociceptive gasotransmitter, and also by PKA that mediates PGE2-induced hyperalgesia. Here we examined and analysed Cav3.2 sensitization via the PGE2/cAMP pathway in NG108-15 cells that express Cav3.2 and produce cAMP in response to PGE2, and its impact on mechanical nociceptive processing in rats. Experimental Approach In NG108-15 cells and rat dorsal root ganglion (DRG) neurons, T-channel-dependent currents (T currents) were measured with the whole-cell patch-clamp technique. The molecular interaction of Cav3.2 with A-kinase anchoring protein 150 (AKAP150) and its phosphorylation were analysed by immunoprecipitation/immunoblotting in NG108-15 cells. Mechanical nociceptive threshold was determined by the paw pressure test in rats. Key Results In NG108-15 cells and/or rat DRG neurons, dibutyryl cAMP (db-cAMP) or PGE2 increased T currents, an effect blocked by AKAP St-Ht31 inhibitor peptide (AKAPI) or KT5720, a PKA inhibitor. The effect of PGE2 was abolished by RQ-00015986-00, an EP4 receptor antagonist. AKAP150 was co-immunoprecipitated with Cav3.2, regardless of stimulation with db-cAMP, and Cav3.2 was phosphorylated by db-cAMP or PGE2. In rats, intraplantar (i.pl.) administration of db-cAMP or PGE2 caused mechanical hyperalgesia, an effect suppressed by AKAPI, two distinct T-channel blockers, NNC 55-0396 and ethosuximide, or ZnCl2, known to inhibit Cav3.2 among T channels. Oral administration of RQ-00015986-00 suppressed the PGE2-induced mechanical hyperalgesia. Conclusion and Implications Our findings suggest that PGE2 causes AKAP-dependent phosphorylation and sensitization of Cav3.2 through the EP4 receptor/cAMP/PKA pathway, leading to mechanical hyperalgesia in rats.
• Antihyperalgesic effect of buprenorphine involves nociceptin/orphanin FQ peptide-receptor activation in rats with spinal nerve injury-induced neuropathy

  Tomoko Takahashi; Kazumasa Okubo; Shota Kojima; Hiroyuki Nishikawa; Motohide Takemura; Maho Tsubota-Matsunami; Fumiko Sekiguchi; Atsufumi Kawabata

  Journal of Pharmacological Sciences 122 (1) 51 - 54 1347-8613 2013 [Refereed]
   

  We evaluated the effect of buprenorphine, a mixed agonist for μ-opioid receptors and nociceptin/orphanin FQ peptide (NOP) receptors, in neuropathic rats, using the paw pressure test. Buprenorphine, administered i.p. at 50, but not 20, μg/kg, exhibited naloxone-reversible analgesic activity in naïve rats. In contrast, buprenorphine at 0.5-20 μg/kg produced a naloxone-sensitive antihyperalgesic effect in the L5 spinal nerve-injured neuropathic rats. Intrathecal injection of [N-Phe1]nociceptin(1-13) NH2, a NOP-receptor antagonist, reversed the effect of buprenorphine in neuropathic rats, but not in naïve rats. Together, buprenorphine suppresses neuropathic hyperalgesia by activating NOP and opioid receptors, suggesting its therapeutic usefulness in treatment of neuropathic pain. © The Japanese Pharmacological Society.
• Involvement of the endogenous hydrogen sulfide/Cav3.2 T-type Ca2+channel pathway in cystitis-related bladder pain in mice

  Maho Matsunami; Takahiro Miki; Kanae Nishiura; Yuko Hayashi; Yasumasa Okawa; Hiroyuki Nishikawa; Fumiko Sekiguchi; Lisa Kubo; Tomoka Ozaki; Toshifumi Tsujiuchi; Atsufumi Kawabata

  BRITISH JOURNAL OF PHARMACOLOGY WILEY-BLACKWELL 167 (4) 917 - 928 0007-1188 2012/10 [Refereed]
   

  BACKGROUND AND PURPOSE Hydrogen sulfide (H2S), generated by enzymes such as cystathionine-?-lyase (CSE) from L-cysteine, facilitates pain signals by activating the Cav3.2 T-type Ca2+ channels. Here, we assessed the involvement of the CSE/H2S/Cav3.2 pathway in cystitis-related bladder pain. EXPERIMENTAL APPROACH Cystitis was induced by i.p. administration of cyclophosphamide in mice. Bladder pain-like nociceptive behaviour was observed and referred hyperalgesia was evaluated using von Frey filaments. Phosphorylation of ERK in the spinal dorsal horn was determined immunohistochemically following intravesical administration of NaHS, an H2S donor. KEY RESULTS Cyclophosphamide caused cystitis-related symptoms including increased bladder weight, accompanied by nociceptive changes (bladder pain-like nociceptive behaviour and referred hyperalgesia). Pretreatment with DL-propargylglycine, an inhibitor of CSE, abolished the nociceptive changes and partly prevented the increased bladder weight. CSE protein in the bladder was markedly up-regulated during development of cystitis. Mibefradil or NNC 550396, blockers of T-type Ca2+ channels, administered after the symptoms of cystitis appeared, reversed the nociceptive changes. Further, silencing of Cav3.2 protein by repeated intrathecal administration of mouse Cav3.2-targeting antisense oligodeoxynucleotides also significantly attenuated the nociceptive changes, but not the increased bladder weight. Finally, the number of cells staining positive for phospho-ERK was increased in the superficial layer of the L6 spinal cord after intravesical administration of NaHS, an effect inhibited by NNC 550396. CONCLUSION AND IMPLICATIONS Endogenous H2S, generated by up-regulated CSE, caused bladder pain and referred hyperalgesia through the activation of Cav3.2 channels, one of the T-type Ca2+ channels, in mice with cyclophosphamide-induced cystitis.
• Hydrogen sulfide-induced mechanical hyperalgesia and allodynia require activation of both Cav3.2 and TRPA1 channels in mice

  Kazumasa Okubo; Midori Matsumura; Yudai Kawaishi; Yuka Aoki; Maho Matsunami; Yasumasa Okawa; Fumiko Sekiguchi; Atsufumi Kawabata

  BRITISH JOURNAL OF PHARMACOLOGY WILEY-BLACKWELL 166 (5) 1738 - 1743 0007-1188 2012/07 [Refereed]
   

  BACKGROUND AND PURPOSE Hydrogen sulfide, a gasotransmitter, facilitates somatic pain signals via activation of Cav3.2 T-type calcium channels in rats. Given evidence for the activation of transient receptor potential ankyrin-1 (TRPA1) channels by H2S, we asked whether TRPA1 channels, in addition to Cav3.2 channels, contribute to the H2S-induced mechanical hyperalgesia and allodynia in mice. EXPERIMENTAL APPROACH Mechanical hyperalgesia and allodynia were evaluated by the von Frey test in mice. Cav3.2 or TRPA1 channels in the sensory neurons were silenced by repeated intrathecal administration of antisense oligodeoxynucleotides in mice. KEY RESULTS Intraplantar administration of NaHS evoked hyperalgesia and allodynia in mice, an effect attenuated or abolished by NNC 550396 or mibefradil, T-type calcium channel blockers, and by ascorbic acid or zinc chloride, known to selectively inhibit Cav3.2 channels, out of the three isoforms of T-type calcium channels. Silencing of Cav3.2 channels in the sensory neurons also prevented the NaHS-induced hyperalgesia and allodynia in mice. The NaHS-induced hyperalgesia and allodynia in mice were significantly suppressed by AP18, a TRPA1 channel blocker, and by silencing of TRPA1 channels in the sensory neurons. CONCLUSIONS AND IMPLICATIONS Mechanical hyperalgesia and allodynia induced by NaHS/H2S required activation of both Cav3.2 and TRPA1 channels in mice.
• Colonic Hydrogen Sulfide-Induced Visceral Pain and Referred Hyperalgesia Involve Activation of Both Ca(v)3.2 and TRPA1 Channels in Mice

  Maho Tsubota-Matsunami; Yumi Noguchi; Yasumasa Okawa; Fumiko Sekiguchi; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 119 (3) 293 - 296 1347-8613 2012/07 [Refereed]
   

  Luminal hydrogen sulfide (H2S), a gasotransmitter, causes colonic pain / referred hyperalgesia in mice, most probably via activation of T-type Ca2+ channels. Here we analyzed the mechanisms for H2S-induced facilitation of colonic pain signals. Intracolonic administration of NaHS, an H2S donor, evoked visceral pain-like nociceptive behavior and referred hyperalgesia in mice, an effect abolished by NNC 55-0396, a selective T-type Ca2+-channel blocker, or by knockdown of Ca(v)3.2. AP18, a TRPA1 blocker, also prevented the NaHS-induced colonic pain and referred hyperalgesia. These findings demonstrate that H2S-induced colonic pain and referred hyperalgesia require activation of both Ca(v)3.2 and TRPA1 channels in mice.
• BIOLOGICAL ACTIVITY OF HELICOBACTER PYLORI COMPONENTS IN MAMMALIAN CELLS: IS IT INDEPENDENT OF PROTEINASE-ACTIVATED RECEPTORS?

  F. Sekiguchi; Y. Matsumoto; Y. Maeda; M. Tsubota-Matsunami; H. Nishikawa; A. Kawabata

  JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY POLISH PHYSIOLOGICAL SOC 63 (6) 571 - 576 0867-5910 2012/12 [Refereed]
   

  To clarify the relationship between Helicobacter pylori (H. pylori), a risk factor for gastritis, peptic ulcer and gastric cancer, and proteinase-activated receptors (PARs) that contribute to inflammatory responses, we determined and characterized the biological activity of H. pylori components in the mammalian cells that express PARs. The activity of H. pylori extracts was assessed in distinct cell lines with high expression of PAR1 (RGM1 cells), PAR2 (A549 cells), or PAR2 and PAR4 (HCT-15 cells). A PAR1-activating peptide (AP), but not H. pylori extracts, caused prostaglandin E-2 (PGE(2)) release in RGM1 cells. On the other hand, H. pylori extracts produced release of PGE2 and interleukin-8 (IL-8) in A549 and HCT-15 cells, respectively, as a PAR2-AP did. The activity of H. pylori extracts in A549 cells was not affected by a proteinase inhibitor or exposure to boiling, but abolished by inhibitors of lipopolysaccharide (LPS), IRAK-1/4 or NF-kappa B. The activity of H. pylori extracts in HCT-15 cells was partially suppressed by boiling or the proteinase inhibitor. In rat platelets that express PAR4 and PAR3, like a PAR4-AP, H. pylori extracts induced aggregation when assessed in platelet rich plasma, an effect unaffected by the proteinase inhibitor, but did not cause aggregation of washed rat platelets that responded to the PAR4-AP or thrombin. The present study thus shows the biological activities of H. pylori extracts in A549 and HCT-15 cells or rat platelets, and suggests that they are not mediated by any PAR-activating proteinases, but may involve the other pathogenic factors including LPS.
• Involvement of ERK in NMDA receptor-independent cortical neurotoxicity of hydrogen sulfide

  Yuko Kurokawa; Fumiko Sekiguchi; Satoko Kubo; Yoshiko Yamasaki; Sachi Matsuda; Yukari Okamoto; Teruki Sekimoto; Anna Fukatsu; Hiroyuki Nishikawa; Toshiaki Kume; Nobuyuki Fukushima; Akinori Akaike; Atsufumi Kawabata

  BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS ACADEMIC PRESS INC ELSEVIER SCIENCE 414 (4) 727 - 732 0006-291X 2011/11 [Refereed]
   

  Hydrogen sulfide (H(2)S), a gasotransmitter, exerts both neurotoxicity and neuroprotection, and targets multiple molecules including NMDA receptors, T-type calcium channels and NO synthase (NOS) that might affect neuronal viability. Here, we determined and characterized effects of NaHS, an H(2)S donor, on cell viability in the primary cultures of mouse fetal cortical neurons. NaHS caused neuronal death, as assessed by LDH release and trypan blue staining, but did not significantly reduce the glutamate toxicity. The neurotoxicity of NaHS was resistant to inhibitors of NMDA receptors, T-type calcium channels and NOS, and was blocked by inhibitors of MEK, but not JNK, p38 MAP kinase, PKC and Src. NaHS caused prompt phosphorylation of ERK and upregulation of Bad, followed by translocation of Bax to mitochondria and release of mitochondrial cytochrome c(1) leading to the nuclear condensation/fragmentation. These effects of NaHS were suppressed by the MEK inhibitor. Our data suggest that the NMDA receptor-independent neurotoxicity of H(2)S involves activation of the MEK/ERK pathway and some apoptotic mechanisms. (C) 2011 Elsevier Inc. All rights reserved.
• INHIBITION OF T-TYPE CALCIUM CHANNELS AND HYDROGEN SULFIDE-FORMING ENZYME REVERSES PACLITAXEL-EVOKED NEUROPATHIC HYPERALGESIA IN RATS

  K. Okubo; T. Takahashi; F. Sekiguchi; D. Kanaoka; M. Matsunami; T. Ohkubo; J. Yamazaki; N. Fukushima; S. Yoshida; A. Kawabata

  NEUROSCIENCE PERGAMON-ELSEVIER SCIENCE LTD 188 148 - 156 0306-4522 2011/08 [Refereed]
   

  Hydrogen sulfide (H,S), a gasotransmitter, facilitates pain sensation by targeting Ca(v)3.2 T-type calcium channels. The H(2)S/Ca(v)3.2 pathway appears to play a role in the maintenance of surgically evoked neuropathic pain. Given evidence that chemotherapy-induced neuropathic pain is blocked by ethosuximide, known to block T-type calcium channels, we examined if more selective T-type calcium channel blockers and also inhibitors of cystathionine-gamma-lyase (CSE), a major H(2)S-forming enzyme in the peripheral tissue, are capable of reversing the neuropathic pain evoked by paclitaxel, an anti-cancer drug. It was first demonstrated that T-type calcium channel blockers, NNC 55-0396, known to inhibit Ca(v)3.1, and mibefradil inhibited T-type currents in Ca(v)3.2-transfected HEK293 cells. Repeated systemic administration of paclitaxel caused delayed development of mechanical hyperalgesia, which was reversed by single intraplantar administration of NNC 550396 or mibefradil, and by silencing of Ca(v)3.2 by antisense oligodeoxynucleotides. Systemic administration of DL-propargylglycine and p-cyanoalanine, irreversible and reversible inhibitors of CSE, respectively, also abolished the established neuropathic hyperalgesia. In the paclitaxel-treated rats, upregulation of Ca(v)3.2 and CSE at protein levels was not detected in the dorsal root ganglia (DRG), spinal cord or peripheral tissues including the hindpaws, whereas H(2)S content in hindpaw tissues was significantly elevated. Together, our study demonstrates the effectiveness of NNC 55-0396 in inhibiting Ca(v)3.2, and then suggests that paclitaxel-evoked neuropathic pain might involve the enhanced activity of T-type calcium channels and/or CSE in rats, but not upregulation of Ca(v)3.2 and CSE at protein levels, differing from the previous evidence for the neuropathic pain model induced by spinal nerve cutting in which Ca(v)3.2 was dramatically upregulated in DRG. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.
• Delayed Production of Arachidonic Acid Contributes to the Delay of Proteinase-Activated Receptor-1 (PAR1)-Triggered Prostaglandin E-2 Release in Rat Gastric Epithelial RGM1 Cells

  Fumiko Sekiguchi; Ai Ohi; Yuma Maeda; Kaori Takaoka; Teruki Sekimoto; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF CELLULAR BIOCHEMISTRY WILEY-BLACKWELL 112 (3) 909 - 915 0730-2312 2011/03 [Refereed]
   

  Proteinase-activated receptor-1 (PAR I), upon activation, exerts prostanoid-dependent gastroprotection, and increases prostaglandin E-2 (PGE(2)) release through cyclooxygenase-2 (COX-2) upregulation in rat gastric mucosal epithelial RGM1 cells. However, there is a big time lag between the PAR I-triggered PG E2 release and COX-2 upregulation in RGM1 cells; that is, the former event takes 18 h to occur, while the latter rapidly develops and reaches a plateau in 6 h. The present study thus aimed at clarifying mechanisms for the delay of PGE2 release after PAR activation in RGM1 cells. Although a PAR1-activating peptide, TFLLR-NH2, alone caused PGE2 release at 18 h, but not 6 h, TFLLR-NH2 in combination with arachidonic acid dramatically enhanced PGE(2) release even for 1-6 h. TFLLR-NH2 plus linoleic acid caused a similar rapid response. CP-24879, a Delta(5)/Delta(6)-desaturase inhibitor, abolished the PGE(2) release induced by TFLLR-NH2 plus linoleic acid, but not by TFLLR-NH2 alone. The TFLLR-NH2-induced PGE2 release was not affected by inhibitors of cytosolic phospholipase A(2) (cPLA(2)), Ca2+-independent PLA(2) (cPLA2) or secretory PLA(2) (sPLA(2)), but was abolished by their mixture or a pan-PLA(2) inhibitor. Among PLA2 isozymes, mRNA of group IIA sPLA(2) (sPLA(2)-IIA) was upregulated following PAR1 stimulation for 6-18 h, whereas protein levels of PGE synthases were unchanged. These data suggest that the delay of PG E2 release after COX-2 upregulation triggered by PAR1 is due to the poor supply of free arachidonic acid at the early stage in RGM1 cells, and that plural isozymes of PLA2 including sPLA2-IIA may complementarily contribute to the liberation of free arachidonic acid. J. Cell. Biochem. 112: 909-915,2011. (C) 2010 Wiley-Liss, Inc.
• The proteinase/proteinase-activated receptor-2/transient receptor potential vanilloid-1 cascade impacts pancreatic pain in mice

  Sachiyo Nishimura; Hiroyasu Ishikura; Maho Matsunami; Yui Shinozaki; Fumiko Sekiguchi; Mitsuhide Naruse; Taisuke Kitamura; Ryukichi Akashi; Kenji Matsumura; Atsufumi Kawabata

  LIFE SCIENCES PERGAMON-ELSEVIER SCIENCE LTD 87 (19-22) 643 - 650 0024-3205 2010/11 [Refereed]
   

  Aims: Proteinase-activated receptor-2 (PAR2) and transient receptor potential vanilloid-1 (TRPV1) are co-localized in the primary afferents, and the trans-activation of TRPV1 by PAR2 activation is involved in processing of somatic pain. Given evidence for contribution of PAR2 to pancreatic pain, the present study aimed at clarifying the involvement of TRPV1 in processing of pancreatic pain by the proteinase/PAR2 pathway in mice. Main methods: Acute pancreatitis was created by repeated administration of cerulein in conscious mice, and the referred allodynia/hyperalgesia was assessed using von Frey filaments. Injection of PAR2 agonises into the pancreatic duct was achieved in anesthetized mice, and expression of Fos in the spinal cord was determined by immunohistochemistry. Key findings: The established referred allodynia/hyperalgesia following cerulein treatment was abolished by post-treatment with nafamostat mesilate, a proteinase inhibitor, and with capsazepine, a TRPV1 antagonist, in mice. Injection of trypsin, an endogenous PAR2 agonist, or SLIGRL-NH(2), a PAR2-activating peptide, into the pancreatic duct caused expression of Fos protein in the spinal superficial layers at T8-T10 levels in the mice. The spinal Fos expression caused by trypsin and by SLIGRL-NH(2) was partially blocked by capsazepine, the former effect abolished by nafamostat mesilate. Significance: Our data thus suggest that the proteinase/PAR2/TRPV1 cascade might impact pancreatic pain, in addition to somatic pain, and play a role in the maintenance of pancreatitis-related pain in mice. (C) 2010 Elsevier Inc. All rights reserved.
• Curcumin Inhibits the Proteinase-Activated Receptor-2-Triggered Prostaglandin E-2 Production by Suppressing Cyclooxygenase-2 Upregulation and Akt-Dependent Activation of Nuclear Factor-kappa B in Human Lung Epithelial Cells

  Kazumi Moriyuki; Fumiko Sekiguchi; Kaori Matsubara; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 114 (2) 225 - 229 1347-8613 2010/10 

  We performed this study to determine if curcumin affects pro-inflammatory responses to activation of proteinase-activated receptor-2 (PAR2) in human pulmonary adenocarcinoma A549 cells. Curcumin completely inhibited the PAR2-triggered prostaglandin E-2 (PGE(2)) production, but notably not interleukin-8 release. Cyclooxygenase-2 (COX-2) upregulation, but not its upstream activation of mitogen-activated protein kinases, caused by PAR2 stimulation was partially inhibited by curcumin. Curcumin inhibited the PAR2-triggered phosphorylation of I-kappa B, an indicator for nuclear factor-kappa B (NF-kappa B) activation, and also its upstream signal Akt, which is known to contribute to PAR2-triggered PGE2 formation, but not COX-2 upregulation. Collectively, curcumin inhibits the PAR2-triggered PGE2 production by suppressing COX-2 upregulation and Akt/NF-kappa B signals in A549 cells.
• Curcumin Inhibits the Proteinase-Activated Receptor-2-Triggered Prostaglandin E-2 Production by Suppressing Cyclooxygenase-2 Upregulation and Akt-Dependent Activation of Nuclear Factor-kappa B in Human Lung Epithelial Cells

  Kazumi Moriyuki; Fumiko Sekiguchi; Kaori Matsubara; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 114 (2) 225 - 229 1347-8613 2010/10 [Refereed]
   

  We performed this study to determine if curcumin affects pro-inflammatory responses to activation of proteinase-activated receptor-2 (PAR2) in human pulmonary adenocarcinoma A549 cells. Curcumin completely inhibited the PAR2-triggered prostaglandin E-2 (PGE(2)) production, but notably not interleukin-8 release. Cyclooxygenase-2 (COX-2) upregulation, but not its upstream activation of mitogen-activated protein kinases, caused by PAR2 stimulation was partially inhibited by curcumin. Curcumin inhibited the PAR2-triggered phosphorylation of I-kappa B, an indicator for nuclear factor-kappa B (NF-kappa B) activation, and also its upstream signal Akt, which is known to contribute to PAR2-triggered PGE2 formation, but not COX-2 upregulation. Collectively, curcumin inhibits the PAR2-triggered PGE2 production by suppressing COX-2 upregulation and Akt/NF-kappa B signals in A549 cells.
• Involvement of Src kinase in T-type calcium channel-dependent neuronal differentiation of NG108-15 cells by hydrogen sulfide

  Takeshi Tarui; Kazuki Fukami; Keita Nagasawa; Shigeru Yoshida; Fumiko Sekiguchi; Atsufumi Kawabata

  JOURNAL OF NEUROCHEMISTRY WILEY-BLACKWELL 114 (2) 512 - 519 0022-3042 2010/07 [Refereed]
   

  P>Hydrogen sulfide (H(2)S), a gasotransmitter, induces neuronal differentiation characterized by neuritogenesis and functional up-regulation of high voltage-activated Ca2+ channels, via activation of T-type Ca2+ channels in NG108-15 cells. We thus analyzed signaling mechanisms for the H(2)S-evoked neuronal differentiation. NaHS, a donor for H(2)S, facilitated T-type Ca2+ channel-dependent membrane currents, an effect blocked by ascorbic acid that selectively inhibits Ca(v)3.2 among three T-type channel isoforms. NaHS, applied once at a high concentration (13.5 mM) or repetitively at a relatively low concentration (1.5 mM), as well as ionomycin, a Ca2+ ionophore, evoked neuritogenesis. The neuritogenesis induced by NaHS, but not by ionomycin, was abolished by mibefradil, a T-type Ca2+ channel blocker. PP2, a Src kinase inhibitor, completely suppressed the neuritogenesis caused by NaHS or ionomycin, while it only partially blocked neuritogenesis caused by dibutyryl cAMP, a differentiation inducer. NaHS, but not dibutyryl cAMP, actually caused phosphorylation of Src, an effect blocked by 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl, an intracellular Ca2+ chelator, mibefradil or ascorbic acid. The up-regulation of high voltage-activated currents in the cells treated with NaHS was also inhibited by PP2. Together, our data reveal that Src kinase participates in the T-type Ca2+ channel-dependent neuronal differentiation caused by NaHS/H(2)S in NG108-15 cells.
• Upregulation of Ca(v)3.2 T-type calcium channels targeted by endogenous hydrogen sulfide contributes to maintenance of neuropathic pain

  Tomoko Takahashi; Yuka Aoki; Kazumasa Okubo; Yumi Maeda; Fumiko Sekiguchi; Kenji Mitani; Hiroyuki Nishikawa; Atsufumi Kawabata

  PAIN ELSEVIER SCIENCE BV 150 (1) 183 - 191 0304-3959 2010/07 [Refereed]
   

  Hydrogen sulfide (H2S) formed from L-cysteine by multiple enzymes including cystathionine-gamma-lyase (CSE) is now considered a gasotransmitter in the mammalian body. Our previous studies have shown that H2S activates/sensitizes Ca(v)3.2 T-type Ca2+ channels, leading to facilitation of somatic and visceral nociception, and that CSE-derived endogenous H2S participates in inflammatory pain. Here, we show novel evidence for involvement of the endogenous H2S-Ca(v)3.2 pathway in neuropathic pain. In the rat subjected to the right L5 spinal nerve cutting (L5SNC), a neuropathic pain model, i.p. administration of DL-propargylglycine (PPG) and beta-cyanoalanine, irreversible and reversible CSE inhibitors, respectively, strongly suppressed the neuropathic hyperalgesia/allodynia. The anti-hyperalgesic effect of PPG was reversed by intraplantar administration of NaHS, a donor for H2S, in the L5SNC rat. Intraplantar administration or topical application of mibefradil, a T-type Ca2+ channel blocker, reversed hyperalgesia in the L5SNC rat. The protein levels of Ca(v)3.2, but not CSE, in the ipsilateral L4, L5 and L6 dorsal root ganglia were dramatically upregulated in the L5SNC rat. Finally, silencing of Ca(v)3.2 in DRG by repeated intrathecal administration of Ca(v)3.2-targeting siRNA significantly attenuated the neuropathic hyperalgesia in the L5SNC rat. In conclusion, our data suggest that Ca(v)3.2 T-type Ca2+ channels in sensory neurons are upregulated and activated/sensitized by CSE-derived endogenous H2S after spinal nerve injury, contributing to the maintenance of neuropathic pain. We thus propose that Ca(v)3.2 and CSE could be targets for the development of therapeutic drugs for the treatment of neuropathic pain. (C) 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
• Opposite effects of two thiazolidinediones, ciglitazone and troglitazone, on proteinase-activated receptor-1-triggered prostaglandin E-2 release

  Kaori Takaoka; Fumiko Sekiguchi; Hidenori Shigi; Yuma Maeda; Hiroyuki Nishikawa; Atsufumi Kawabata

  TOXICOLOGY ELSEVIER IRELAND LTD 268 (1-2) 40 - 45 0300-483X 2010/01 [Refereed]
   

  Thiazolidinediones, known as peroxisome proliferator-activated receptor-gamma (PPAR gamma) agonists, may modify prostaglandin formation and exert gastroprotective effects. Since activation of proteinase-activated receptor-1 (PAR1) reveals endogenous prostanoid-dependent gastroprotection, we investigated if two thiazolidinediones, ciglitazone and troglitazone, modulate the prostaglandin E-2 (PGE(2)) release caused by activation of PAR1 in normal rat gastric mucosal epithelial RGM1 cells. Ciglitazone dramatically facilitated the PAR1-triggered PGE(2) production and cyclooxygenase-2 (COX-2) upregulation, although it had no effect by itself. In contrast, troglitazone suppressed the PARI-triggered PGE2 production and COX-2 upregulation. Either effect of ciglitazone and troglitazone was resistant to GW9662, a PPAR gamma antagonist. The facilitation of the PGE(2) release by ciglitazone was blocked by inhibitors of MEK, p38 MAP kinase (p38MAPK) and PI3-kinase (PI3K), but not JNK. Nonetheless, ciglitazone failed to enhance the PAR1-triggered phosphorylation of ERK and p38MAPK. In conclusion, ciglitazone and troglitazone, exert opposite effects on the PARI-triggered PGE(2) production and COX-2 upregulation by targeting molecules other than PPAR gamma. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
• Proteinase-Activated Receptor-2-Triggered Prostaglandin E-2 Release, but Not Cyclooxygenase-2 Upregulation, Requires Activation of the Phosphatidylinositol 3-Kinase/Akt/Nuclear Factor-kappa B Pathway in Human Alveolar Epithelial Cells

  Kazumi Moriyuki; Fumiko Sekiguchi; Kaori Matsubara; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 111 (3) 269 - 275 1347-8613 2009/11 

  Proteinase-activated receptor-2 (PAR2) triggers upregulation of cyclooxygenase-2 (COX-2) and prostaglandin E-2 (PGE(2)) formation in human alveolar epithelial A549 cells. This COX-2 upregulation appears to involve the Src/epidermal growth factor (EGF) receptor/p38 MAP kinase (p38MAPK) pathway and also the cAMP-response element-binding protein (CREB) pathway. Here, we investigated the roles of nuclear factor-kappa B (NF-kappa B)-related signals in the PAR2-triggered PGE(2) release/COX-2 upregulation in A549 cells. The PAR2-triggered PGE2 release was clearly blocked by an inhibitor of the NF-kappa B pathway. Stimulation of PAR2 actually caused phosphorylation of inhibitor-kappa B, an indicator of NF-kappa B activation, an effect being blocked by inhibitors of MEK, phosphatidylinositol 3-kinase (PI3-kinase), and Akt, but little or not by inhibitors of p38MAPK and JNK. Stimulation of PAR2 also caused phosphorylation of Akt, an effect suppressed by inhibitors of PI3-kinase and MEK. Nonetheless, the PAR2-triggered upregulation of COX-2 was resistant to inhibitors of NF-kappa B, PI3-kinase, and Akt, but was attenuated by inhibitors of MEK and JNK. Stimulation of PAR2 induced phosphorylation of CREB, an effect abolished by an inhibitor of MEK but not inhibitors of p38MAPK and EGF receptor. These findings demonstrate that the MEK / ERK / PI3-kinase / Akt / NF-kappa B pathway is involved in PAR2-triggered PGE2 formation, but not upregulation of COX-2 that is dependent on activation of ERK/CREB and JNK in addition to p38MAPK.
• Proteinase-Activated Receptor-2-Triggered Prostaglandin E-2 Release, but Not Cyclooxygenase-2 Upregulation, Requires Activation of the Phosphatidylinositol 3-Kinase/Akt/Nuclear Factor-kappa B Pathway in Human Alveolar Epithelial Cells

  Kazumi Moriyuki; Fumiko Sekiguchi; Kaori Matsubara; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF PHARMACOLOGICAL SCIENCES JAPANESE PHARMACOLOGICAL SOC 111 (3) 269 - 275 1347-8613 2009/11 [Refereed]
   

  Proteinase-activated receptor-2 (PAR2) triggers upregulation of cyclooxygenase-2 (COX-2) and prostaglandin E-2 (PGE(2)) formation in human alveolar epithelial A549 cells. This COX-2 upregulation appears to involve the Src/epidermal growth factor (EGF) receptor/p38 MAP kinase (p38MAPK) pathway and also the cAMP-response element-binding protein (CREB) pathway. Here, we investigated the roles of nuclear factor-kappa B (NF-kappa B)-related signals in the PAR2-triggered PGE(2) release/COX-2 upregulation in A549 cells. The PAR2-triggered PGE2 release was clearly blocked by an inhibitor of the NF-kappa B pathway. Stimulation of PAR2 actually caused phosphorylation of inhibitor-kappa B, an indicator of NF-kappa B activation, an effect being blocked by inhibitors of MEK, phosphatidylinositol 3-kinase (PI3-kinase), and Akt, but little or not by inhibitors of p38MAPK and JNK. Stimulation of PAR2 also caused phosphorylation of Akt, an effect suppressed by inhibitors of PI3-kinase and MEK. Nonetheless, the PAR2-triggered upregulation of COX-2 was resistant to inhibitors of NF-kappa B, PI3-kinase, and Akt, but was attenuated by inhibitors of MEK and JNK. Stimulation of PAR2 induced phosphorylation of CREB, an effect abolished by an inhibitor of MEK but not inhibitors of p38MAPK and EGF receptor. These findings demonstrate that the MEK / ERK / PI3-kinase / Akt / NF-kappa B pathway is involved in PAR2-triggered PGE2 formation, but not upregulation of COX-2 that is dependent on activation of ERK/CREB and JNK in addition to p38MAPK.
• Rhodanese, but not cystathionine-gamma-lyase, is associated with dextran sulfate sodium-evoked colitis in mice: A sign of impaired colonic sulfide detoxification?

  Eiichi Taniguchi; Maho Matsunami; Takeshi Kimura; Daiki Yonezawa; Tsuyoshi Ishiki; Fumiko Sekiguchi; Hiroyuki Nishikawa; Yuma Maeda; Hiroyasu Ishikura; Atsufumi Kawabata

  TOXICOLOGY ELSEVIER IRELAND LTD 264 (1-2) 96 - 103 0300-483X 2009/10 [Refereed]
   

  Clinical studies suggest that colonic luminal hydrogen sulfide (H(2)S), produced by sulfate-reducing bacteria or through other pathways, might be involved in the pathogenesis of inflammatory bowel disease (IBD). Nonetheless, this hypothesis has been poorly investigated by basic studies using laboratory animals. We thus focused on two enzymes, cystathionine-gamma-lyase (CSE) that generates H(2)S from L-cysteine, and rhodanese that directly or indirectly detoxifies H(2)S, particularly in relation to the colitis induced by dextran sulfate sodium (DSS) in mice. CSE was a major H(2)S-forming enzyme in colonic and renal homogenates from mice and rats, and the rhodanese activity was also detectable in both tissues. Colitis-related symptoms including decreased body weight gain, diarrhea, hematochezia and shortening of colon length were observed in the mice drinking DSS. Those symptoms were not or only slightly attenuated by repeated administration of a CSE inhibitor. CSE activity and protein levels in the colonic tissue did not notably change in the mice with colitis. In contrast, the activity and protein/mRNA levels of rhodanese in the colon, but not kidney, significantly decreased nearly in parallel with the development of colitis, followed by elevation of rhodanese activity in red blood cells (RBCs). These data show that rhodanese, but not CSE, is associated with DSS-induced colitis in mice, leading to a hypothesis that impaired detoxification of H(2)S due to down-regulation or suppression of colonic rhodanese is involved in IBD. The delayed enhancement of rhodanese activity in RBCs, a possible compensative event, might be available as a disease marker for IBD. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
• Hydrogen sulfide as a novel mediator for pancreatic pain in rodents

  S. Nishimura; O. Fukushima; H. Ishikura; T. Takahashi; M. Matsunami; T. Tsujiuchi; F. Sekiguchi; M. Naruse; Y. Kamanaka; A. Kawabata

  GUT B M J PUBLISHING GROUP 58 (6) 762 - 770 0017-5749 2009/06 

  Objective: Hydrogen sulfide (H(2)S) is formed from L-cysteine by multiple enzymes including cystathionine-gamma-lyase (CSE) in mammals, and plays various roles in health and disease. Recently, a pronociceptive role for H(2)S in the processing of somatic pain was identified. Here, the involvement of H(2)S in pancreatic pain is examined. Methods: Anaesthetised rats or mice received an injection of NaHS, a donor for H(2)S, or capsaicin into the pancreatic duct, and the expression of spinal Fos protein was detected by immunohistochemistry. Pancreatitis was created by 6 hourly doses of caerulein in unanaesthetised mice, and pancreatitis-related allodynia/hyperalgesia was evaluated using von Frey hairs. CSE activity and protein levels in pancreatic tissues were measured using the colorimetric method and western blotting, respectively. Results: Either NaHS or capsaicin induced the expression of Fos protein in the superficial layers of the T8 and T9 spinal dorsal horn of rats or mice. The induction of Fos by NaHS but not capsaicin was abolished by mibefradil, a T-type Ca(2+) channel blocker. In conscious mice, repeated doses of caerulein produced pancreatitis accompanied by abdominal allodynia/hyperalgesia. Pretreatment with an inhibitor of CSE prevented the allodynia/hyperalgesia, but not the pancreatitis. A single dose of mibefradil reversed the established pancreatitis-related allodynia/hyperalgesia. Either the activity or protein expression of pancreatic CSE increased after the development of caerulein-induced pancreatitis in mice. Conclusions: The data suggest that pancreatic NaHS/H(2)S most probably targets T-type Ca(2+) channels, leading to nociception, and that endogenous H(2)S produced by CSE and possibly T-type Ca(2+) channels are involved in pancreatitis-related pain.
• Hyperalgesia induced by spinal and peripheral hydrogen sulfide: Evidence for involvement of Ca(v)3.2 T-type calcium channels

  Yumi Maeda; Yuka Aoki; Fumiko Sekiguchi; Maho Matsunami; Tomoko Takahashi; Hiroyuki Nishikawa; Atsufumi Kawabata

  PAIN ELSEVIER SCIENCE BV 142 (1-2) 127 - 132 0304-3959 2009/03 [Refereed]
   

  Hydrogen sulfide (H2S), a gasotransmitter, facilitates membrane currents through T-type Ca2+ channels, and intraplantar (i.pl.) administration of NaHS, a donor of H2S, causes prompt hyperalgesia in rats. In this. context, we asked whether intrathecal (i.t.) administration of NaHS could mimic the hyperalgesic effect of i.pl. NaHS in rats, and then examined if Ca(v)3.2 isoform of T-type Ca2+ channels contributed to the pronociceptive effects of i.t. and i.pl. NaHS. Either i.t. or i.pl. administration of NaHS rapidly decreased nociceptive threshold in rats, as determined by the paw pressure method. The hyperalgesia caused by i.t. and i.pl. NaHS was abolished by co-administration of mibefradil, a pan-T-type Ca2+ channel inhibitor, and also Suppressed by pretreatment with i.t. and i.pl, zinc chloride, known to preferentially inhibit Ca(v)3.2 among T-type Ca2+ channel isoforms, respectively. Repeated i.t. administration of antisense oligodeoxynucleotides (ODNs) targeting rat Cav3.2, but not mismatch ODNs, caused silencing of Ca(v)3.2 protein in the dorsal root ganglia and spinal cord, and then attenuated the hyperalgesia induced by either i.t. or i.pl, NaHS. Our findings thus establish that spinal and peripheral NaHS/H2S activates or sensitizes Ca(v)3.2 T-type Ca2+ channels expressed in the primary afferents and/or spinal nociceptive neurons, leading to sensitization of nociceptive processing and hyperalgesia. (C) 2008 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
• Hydrogen sulfide evokes neurite outgrowth and expression of high-voltage-activated Ca2+ currents in NG108-15 cells: involvement of T-type Ca2+ channels

  Keita Nagasawa; Takeshi Tarui; Shigeru Yoshida; Fumiko Sekiguchi; Maho Matsunami; Ai Ohi; Kazuki Fukami; Seiji Ichida; Hiroyuki Nishikawa; Atsufumi Kawabata

  JOURNAL OF NEUROCHEMISTRY WILEY-BLACKWELL 108 (3) 676 - 684 0022-3042 2009/02 [Refereed]
   

  We investigated if stimulation of T-type Ca2+ channels with sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), could cause neuronal differentiation of NG108-15 cells. Like dibutyryl cyclic AMP (db-cAMP), treatment with NaHS at 1.5-13.5 mM for 16 h enhanced neurite outgrowth in a concentration-dependent manner. Synergistic neuritogenic effect was obtained in the cells stimulated with NaHS in combination with db-cAMP at subeffective concentrations. Exposure to NaHS or db-cAMP for 2 days resulted in enhancement of expression of high-voltage-activated currents consisting of N-, P/Q-, L- and also other types, but not of T-type currents. Mibefradil, a pan-T-type channel blocker, abolished the neuritogenesis induced by NaHS, but not by db-cAMP. The NaHS-evoked neuritogenesis was also completely blocked by pretreatment with BAPTA/AM, a chelator of intracellular Ca2+, and by zinc chloride at a concentration known to selectively inhibit Ca(v)3.2 isoform of T-type Ca2+ channels, but not Ca(v)3.1 or Ca(v)3.3. Further, l-ascorbate, recently proven to selectively inhibit Ca(v)3.2, abolished the neuritogenic effect of NaHS, but not db-cAMP. Our data thus demonstrate that NaHS/H2S is a novel inducer of neuronal differentiation in NG108-15 cells, as characterized by neuritogenesis and expression of high-voltage-activated currents, and suggest the involvement of T-type Ca2+ channels, especially Ca(v)3.2.
• PAR2 triggers IL-8 release via MEK/ERK and PI3-kinase/Akt pathways in GI epithelial cells

  Yusuke Tanaka; Fumiko Sekiguchi; Hao Hong; Atsufumi Kawabata

  BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS ACADEMIC PRESS INC ELSEVIER SCIENCE 377 (2) 622 - 626 0006-291X 2008/12 [Refereed]
   

  Proteinase-activated receptor-2 (PAR2) plays pro-inflammatory roles in many organs including the gastrointestinal (GI) tract. To clarify the downstream pro-inflammatory signaling of PAR2 in the GI tract, we examined interleukin-8 (IL-8) release and the underlying cellular signaling following PAR2 stimulation in human colorectal cancer-derived HCT-15 cells and human gastric adenocarcinoma-derived MKN-45 cells. A PAR2-activating peptide, but not a PAR2-inactive scrambled peptide or a PAR1 - activating peptide, caused IL-8 elease in these GI epithelial cells. The PAR2-triggered IL-8 release was suppressed by inhibitors of MEK (U0126) or PI3-kinase (LY294002), and PAR2 stimulation indeed activated the downstream kinases, ERK and Akt. U0126 blocked the phosphorylation of ERK, but not Akt, and LY294002 blocked the phosphorylation of Akt, but not ERK. Together, PAR2 triggers IL-8 release via two independent signaling pathways, MEK/ERK and PI3-kinase/Akt, suggesting a role of PAR2 as a pro-inflammatory receptor in the GI tract. (C) 2008 Elsevier Inc. All rights reserved.
• プロテアーゼ活性化受容体 Protease-activated receptor (PAR)

  松波 真帆; 関口 富美子; 川畑 篤史

  日本薬理学雑誌「くすりとからだ」 キーワード解 128 434 - 436 2008/12 [Invited]
  
• Protease-activated receptor シグナル

  関口 富美子; 川畑 篤史

  救急・集中治療 20 (9-10) 1297 - 1303 2008/11
• Gastrointestinal roles for proteinase-activated receptors in health and disease

  A. Kawabata; M. Matsunami; F. Sekiguchi

  BRITISH JOURNAL OF PHARMACOLOGY NATURE PUBLISHING GROUP 153 S230 - S240 0007-1188 2008/03 

  It has been almost a decade since the molecular cloning of all four members of the proteinase-activated receptor ( PAR) family was completed. This unique family of G protein-coupled receptors (GPCRs) mediates specific cellular actions of various endogenous proteinases including thrombin, trypsin, tryptase, etc. and also certain exogenous enzymes. Increasing evidence has been clarifying the emerging roles played by PARs in health and disease. PARs, particularly PAR1 and PAR2, are distributed throughout the gastrointestinal (GI) tract, modulating various GI functions. One of the most important GI functions of PARs is regulation of exocrine secretion in the salivary glands, pancreas and GI mucosal epithelium. PARs also modulate motility of GI smooth muscle, involving multiple mechanisms. PAR2 appears to play dual roles in pancreatitis and related pain, being pro-inflammatory/pro-nociceptive and anti-inflammatory/anti-nociceptive. Similarly, dual roles for PAR1 and PAR2 have been demonstrated in mucosal inflammation/damage throughout the GI tract. There is also fundamental and clinical evidence for involvement of PAR2 in colonic pain. PARs are thus considered key molecules in regulation of GI functions and targets for development of drugs for treatment of various GI diseases.
• Evidence that PAR2-triggered prostaglandin E-2 (PGE(2)) formation involves the ERK-cytosolic phospholipase A(2)-COX-1-microsomal PGE synthase-1 cascade in human lung epithelial cells

  Mami Nagataki; Kazumi Moriyuki; Fumiko Sekiguchi; Atsufumi Kawabata

  CELL BIOCHEMISTRY AND FUNCTION JOHN WILEY & SONS LTD 26 (2) 279 - 282 0263-6484 2008/03 [Refereed]
   

  We investigated possible involvement of three isozymes of prostaglandin E synthase (PGES), microsomal PGES-1 (mPGES-1), mPGES-2 and cytosolic PGES (cPGES) in COX-2-dependent prostaglandin E-2 (PGE(2)) formation following proteinase-activated receptor-2 (PAR2) stimulation in human lung epithelial cells. PAR2 stimulation up-regulated mPGES-1 as well as COX-2, but not mPGES-2 or cPGES, leading to PGE2 formation. The PAR2-triggered up-regulation of mPGES-1 was suppressed by inhibitors of COX-1, cytosolic phospholipase A(2) (cPLA(2)) and MEK, but not COX-2. Finally, a selective inhibitor of mPGES-1 strongly suppressed the PAR2-evoked PGE(2) formation. PAR2 thus appears to trigger specific up-regulation of mPGES-1 that is dependent on prostanoids formed via the MEK/ERK/cPLA(2)/COX-1 pathway, being critical for PGE(2) formation. Copyright (c) 2007 John Wiley & Sons, Ltd.
• Gastrointestinal roles for proteinase-activated receptors in health and disease

  A. Kawabata; M. Matsunami; F. Sekiguchi

  BRITISH JOURNAL OF PHARMACOLOGY NATURE PUBLISHING GROUP 153 S230 - S240 0007-1188 2008/03 [Invited]
   

  It has been almost a decade since the molecular cloning of all four members of the proteinase-activated receptor ( PAR) family was completed. This unique family of G protein-coupled receptors (GPCRs) mediates specific cellular actions of various endogenous proteinases including thrombin, trypsin, tryptase, etc. and also certain exogenous enzymes. Increasing evidence has been clarifying the emerging roles played by PARs in health and disease. PARs, particularly PAR1 and PAR2, are distributed throughout the gastrointestinal (GI) tract, modulating various GI functions. One of the most important GI functions of PARs is regulation of exocrine secretion in the salivary glands, pancreas and GI mucosal epithelium. PARs also modulate motility of GI smooth muscle, involving multiple mechanisms. PAR2 appears to play dual roles in pancreatitis and related pain, being pro-inflammatory/pro-nociceptive and anti-inflammatory/anti-nociceptive. Similarly, dual roles for PAR1 and PAR2 have been demonstrated in mucosal inflammation/damage throughout the GI tract. There is also fundamental and clinical evidence for involvement of PAR2 in colonic pain. PARs are thus considered key molecules in regulation of GI functions and targets for development of drugs for treatment of various GI diseases.
• Signal transduction for formation/release of interleukin-8 caused by a PAR2-activating peptide in human lung epithelial cells

  Kazumi Moriyuki; Mami Nagataki; Fumiko Sekiguchi; Hiroyuki Nishikawa; Atsufumi Kawabata

  REGULATORY PEPTIDES ELSEVIER SCIENCE BV 145 (1-3) 42 - 48 0167-0115 2008/01 [Refereed]
   

  Proteinase-activated receptor-2 (PAR2) plays a dual role in the respiratory system, being pro- and anti-inflammatory. In human lung epithelial cells (A549), PAR2 activation causes release of interleukin-8 (IL-8) in addition to prostaglandin E-2 (PGE(2)). In the present study, we thus investigated PAR2-triggered signal transduction pathways causing IL-8 formation in A549 cells. SLIGRL-NH2, a PAR2-activating peptide, but not LSIGRL-NH2,, a scrambled peptide, elicited release of IL-8 from A549 cells for 18 h, as measured by the ELISA method, an effect being suppressed by inhibitors of MEK, JNK, EGF receptor-tyrosine kinase (EGFR-TK), Src, pan-tyrosine kinases and protein kinase C, but not p38 MAP kinase or cyclooxygenase. SLIGRL-NH2, also up-regulated IL-8 at protein and mRNA levels, as determined by Western blotting and RTPCR, respectively. The PAR2-triggered up-regulation of IL-8 protein and mRNA was blocked by an inhibitor of MEK, but not clearly by inhibitors of JNK and EGFR-TK. SLIGRL-NH2 actually phosphorylated JNK as well as ERK, the JNK activation being resistant to inhibitors of Src, pan-tyrosine kinases, protein kinase C and EGFR-TK. Our data suggest that PAR2-triggerd IL-8 formation involves transcriptional upregulation of IL-8 via the MEK-ERK pathway, while the JNK and EGF receptor pathways might rather contribute to a post-transcriptional process for the release of IL-8. (c) 2007 Elsevier B.V. All rights reserved.
• Proteinase-activated receptors in the gastrointestinal system: A functional linkage to prostanoids

  F. Sekiguchi; K. Takaoka; A. Kawabata

  Inflammopharmacology 15 (6) 246 - 251 0925-4692 2007/12 [Refereed][Invited]
   

  Proteinase-activated receptors (PARs), G protein-coupled receptors, play critical roles in the alimentary system. Increasing evidence suggests that endogenous prostaglandins (PGs) mediate some of PARs' gastrointestinal functions. Systemic administration of the PAR1 agonist protects against gastric mucosal injury through PG formation in rats. PGs also appear to contribute, at least in part, to enhancement of gastric mucosal blood flow and suppression of gastric acid secretion by PAR1 activation. There is also evidence for involvement of PGs in modulation of gastrointestinal motility by PAR1 or PAR2. Importantly, modulation of ion transport by PAR1 or PAR2 in the intestinal mucosal epithelium is largely mediated by PGs. Studies using gastric and intestinal mucosal epithelial cell lines imply that the PAR1-triggered formation of PGs involves multiple signaling pathways including Src, EGF receptor trans-activation and activation of MAP kinases. Collectively, a functional linkage of PAR1 and/or PAR2 to PGs is considered important in the gastrointestinal system. © 2007 Springer.
• Hydrogen sulfide inhibits activity of three isoforms of recombinant nitric oxide synthase

  Atoko Kubo; Yuko Kurokawa; Ichiko Doe; Takashi Masuko; Fumiko Sekiguchi; Atsufumi Kawabata

  TOXICOLOGY ELSEVIER IRELAND LTD 241 (1-2) 92 - 97 0300-483X 2007/11 [Refereed]
   

  To clarify the presence of cross-talk between H2S and NO, we investigated effect of NaHS, an H2S donor, on activity of recombinant NO synthase (NOS) isoforms. Activity of all nNOS, iNOS and eNOS was inhibited by NaHS (IC50: 0.13-0.21 mM). In contrast, Na2SO3, L-Cysteine and threo-1,4-dimercapto-2,3-butanediol, a reductant, exerted poor inhibition of NOS activity. Increasing concentrations of tetrahydrobiopterin (BH4) reversed the NaHS inhibition of nNOS and eNOS, but not iNOS. Our data thus demonstrate inhibition of three NOS isoforms by NaHS/H2S, and suggest involvement of interaction of NaHS/H2S with BH4 in inhibition of nNOS and eNOS, but not iNOS. (C) 2007 Elsevier Ireland Ltd. All rights reserved.
• A protective role of hydrogen sulfide against oxidative stress in rat gastric mucosal epithelium

  Daiki Yonezawa; Fumiko Sekiguchi; Misato Miyamoto; Eiichi Taniguchi; Masami Honjo; Takashi Masuko; Hiroyuki Nishikawa; Atsufumi Kawabata

  TOXICOLOGY ELSEVIER IRELAND LTD 241 (1-2) 11 - 18 0300-483X 2007/11 [Refereed]
   

  We investigated effect of hydrogen sulfide (H2S) on oxidative stress-caused cell death in gastric mucosal epithelial cells. In rat normal gastric epithelial RGM1 cells, NaHS, a H2S donor, at 1.5 mM strongly suppressed hydrogen peroxide (H2O2)-caused cell death, while it slightly augmented the H2O2 toxicity at 0.5-1 mM. The protective effect of NaHS was abolished by inhibitors of MEK or JNK, but not of p38 MAP kinase. NaHS at 1.5 mM actually phosphorylated ERK and JNK in RGM1 cells. Glibenclamide, an ATP-sensitive K+ (K-ATP(+)) channel inhibitor, did not affect the protective effect of NaHS, although mRNAs for K(ATP)(+)channel subunits, Kir6.1 and SUR1, were detected in RGM1 cells. In anesthetized rats, oral administration of NaHS protected against gastric mucosal lesion caused by ischemia-reperfusion. These results suggest that NaHS/H2S may protect gastric mucosal epithelial cells against oxidative stress through stimulation of MAP kinase pathways, a therapeutic dose range being very narrow. (C) 2007 Elsevier Ireland Ltd. All rights reserved.
• Hydrogen sulfide as a novel nociceptive messenger

  Atsufumi Kawabata; Tsuyoshi Ishiki; Kelta Nagasawa; Shigeru Yoshida; Yumi Maeda; Tomoko Takahashi; Fumiko Sekiguchi; Tetsuyuki Wada; Seiji Ichida; Hiroyuki Nishikawa

  PAIN ELSEVIER SCIENCE BV 132 (1-2) 74 - 81 0304-3959 2007/11 [Refereed]
   

  Hydrogen sulfide (H2S), an endogenous gasotransmitter, modulates various biological events such as inflammation in the mammalian body. The present study investigated possible involvement of H2S in peripheral nociceptive processing. Intraplantar (i.pl.) administration of NaHS, a H2S donor, produced prompt hyperalgesia in rats, accompanied by expression of Fos in the spinal dorsal horn. The H2S-evoked hyperalgesia was blocked by 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB), an oxidizing agent, or ethosuximide and mibefradil, T-type Ca2+ channel inhibitors. L-Cysteine, an endogenous source for H2S, given i.pl., also elicited hyperalgesia, an effect being abolished by DL-propargylglycine (PPG) and beta-cyanoalanine (BCA), inhibitors of cystathionine-gamma-lyase, a H2S synthesizing enzyme. PPG and/or BCA partially inhibited the hyperalgesia induced by i.pl. lipopolysaccharide, an effect being reversed by i.pl. NaHS. In the patch-clamp study using undifferentiated NG108-15 cells that express T-type, but not other types, of Ca2+ channels, NaHS enhanced the currents through the T-type channels, an effect being blocked by DTNB. Thus, H2S appears to function as a novel nociceptive messenger through sensitization of T-type Ca2+ channels in the peripheral tissues, particularly during inflammation. (C) 2007 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
• The proteinase inhibitor camostat mesilate suppresses pancreatic pain in rodents

  Hiroyasu Ishikura; Sachiyo Nishimura; Maho Matsunami; Toshifumi Tsujiuchi; Tsuyoshi Ishiki; Fumiko Sekiguchi; Mitsuhide Naruse; Toshio Nakatani; Yoshihisa Kamanaka; Atsufumi Kawabata

  LIFE SCIENCES PERGAMON-ELSEVIER SCIENCE LTD 80 (21) 1999 - 2004 0024-3205 2007/05 [Refereed]
   

  Camostat mesilate, an orally available proteinase inhibitor, is clinically used for treatment of pancreatitis. Given recent evidence that pancreatic proteinases including trypsin and/or proteinase-activated receptor-2 (PAR2) might be involved in pancreatic pain, we examined if camostat mesilate could suppress spinal Fos expression, a marker for neuronal activation, following specific application of trypsin to the pancreas, and pancreatitis-related referred allodynia. Trypsin, administered into the pancreatic duct, caused delayed expression of Fos proteins in the superficial layer of the bilateral T8 and T9 spinal dorsal horns in rats. The trypsin-induced spinal Fos expression was completely abolished by oral preadministration of camostat mesilate at 300 mg/kg. After hourly repeated (6 times in total) administration of caerulein, mice showed typical symptoms of pancreatitis, accompanied by mechanical allodynia in the upper abdomen (i.e., referred hyperalgesia/allodynia), as assessed by use of von Frey filaments. Camostat mesilate at 100-300 mg/kg, given orally twice before the 1st and 4th doses of cacrulein, abolished the pancreatitis-related abdominal allodynia, while it partially prevented the inflammatory signs. The same doses of camostat mesilate, when administered once after the final dose of caerulein, also revealed significant anti-allodynic effect. These data suggest that camostat mesilate prevents and/or depresses pancreatitis-induced pain and/or referred hyperalgesia/allodynia, in which proteinases including trypsin would play a critical role. (C) 2007 Elsevier Inc. All rights reserved.
• Mechanisms for prostaglandin E-2 formation caused by proteinase-activated receptor-1 activation in rat gastric mucosal epithelial cells

  Fumiko Sekiguchi; Shino Saito; Kaori Takaoka; Hitomi Hayashi; Mami Nagataki; Keita Nagasawa; Hiroyuki Nishikawa; Hirofumi Matsui; Atsufumi Kawabata

  BIOCHEMICAL PHARMACOLOGY PERGAMON-ELSEVIER SCIENCE LTD 73 (1) 103 - 114 0006-2952 2007/01 [Refereed]
   

  Proteinase-activated receptor-1 (PAR1), a thrombin receptor, plays a protective role in gastric mucosa via prostanoid formation. Thus, we studied effects of PAR1 stimulation on prostaglandin E-2 (PGE(2)) formation in rat normal gastric mucosal epithelial RGM1 cells and analyzed the underlying signal transduction mechanisms. The PARI-activating peptide (PAR1-AP) and thrombin increased PGE(2) release from RGM1 cells for 18 h, an effect being suppressed by inhibitors of COX-1, COX-2, MEK, p38 MAP kinase (p38 MAPK), protein kinase C (PKC), Src and EGF receptor-tyrosine kinase (EGFR-TK), but not JNK and matrix metalloproteinase (MMP)/a disintegrin and metalloprotemases (ADAMs). PAR1-AP caused persistent (6 h or more) and transient (5 min) phosphorylation of ERK and p38 MAPK, respectively, followed by delayed reinforcement at 18 h. PAR1-AP up-regulated COX-2 in a manner dependent on MEK and EGFR-TK, but not p38 MAPK. The PARI-mediated persistent ERK phosphorylation was reduced by inhibitors of Src and EGFR-TK. PAR1-AP actually phosphorylated EGF receptors and up-regulated mRNA for heparin-binding-EGF (HB-EGF), the latter effect being blocked by inhibitors of Src, EGFR-TK and MEK. Heparin, an inhibitor for HB-EGF, suppressed PAR1-mediated PGE2 formation and persistent ERK phosphorylation. These results suggest that PAR1 up-regulates COX-2 via persistent activation of MEK/ERK that is dependent on EGFR-TK activation following induction of HB-EGF, leading to PGE(2) formation. In addition, our data also indicate involvement of COX-1, PKC and p38 MAPK in PAR1-triggered PGE(2) formation. PAR1, thus stimulates complex multiple signaling pathways responsible for PGE(2) formation in RGM1 cells. (c) 2006 Elsevier Inc. All rights reserved.
• Protease-activated receptor (PAR)

  MATSUNAMI Maho; SEKIGUCHI Fumiko; KAWABATA Atsufumi

  Folia pharmacologica Japonica 日本薬理学会 128 (6) 434 - 436 0015-5691 2006/12
• Distinct activity of peptide mimetic intracellular ligands (pepducins) for proteinase-activated receptor-1 in multiple cells/tissues

  Satoko Kubo; Tsuyoshi Ishiki; Ichiko Doe; Fumiko Sekiguchi; Hiroyuki Nishikawa; Kenzo Kawai; Hirofumi Matsui; Atsufumi Kawabata

  SIGNAL TRANSDUCTION PATHWAYS, PT B BLACKWELL PUBLISHING 1091 445 - 459 0077-8923 2006 [Refereed]
   

  Proteinase-activa ted receptor-1 (PAR1), a G protein-coupled receptor (GPCR) for thrombin, can be activated not only by PARlactivating peptides (PAR1APs) based on the N-terminal cryptic tethered ligand sequence but also by an N-palmitoylated (Pal) peptide, Pal-RCLSSSAVANRSKKSRALF-amide (P1pal-19), based on the intracellular loop 3 of PARI, designated pepducin, in human platelets or PAR1-transfected cells. The present article evaluated the actions of P1pal-19 and also the shorter peptide, Pal-RCLSSSAVANRS-amide (P1pal-12), known as a possible PAR1 antagonist, in multiple cells/tissues that naturally express PAR1. P1pal-19 as well as a PAR1AP, TFLLR-amide, evoked cytosolic Ca2+ mobilization in cultured human lung epithelial cells (A549) and rat gastric mucosal epithelial cells (RGM1). P1pal-19 and TFLLR-amide, but not a PAR2-activating peptide, SLIGRL-amide, caused delayed prostaglandin E-2 formation in RGM1 cells. P1pal-19, like TFLLR-amide, produced endothelial NO-dependent relaxation in rat aorta and epithelial prostanoid-dependent relaxation in mouse bronchus. The P1pal-19-induced relaxation remained constant even after desensitization of PARI with TFLLR-amide in either tissue. P1pal-19 failed to mimic the contractile effects of TFLLR-amide in the endothelium-denuded preparations of rat aorta or superior mesenteric artery and the rat gastric longitudinal smooth muscle strips. P1pal12 partially inhibited the vasorelaxation caused by TFLLR-amide and P1pal-19, but not SLIGRL-amide, in the rat. aorta. Our data thus indicate that P1pal-19 is capable of mimicking the effects of PAR1APs in the endothelial and epithelial, but not smooth muscle, cells/tissues, and suggest that P1pal-12 may act as a PAR1 antagonist in the vascular endothelium.
• Antiallodynic effect of etidronate, a bisphosphonate, in rats with adjuvant-induced arthritis: Involvement of ATP-sensitive K+ channels

  Atsufumi Kawabata; Naoyuki Kawao; Yoshimi Hironaka; Tsuyoshi Ishiki; Maho Matsunami; Fumiko Sekiguchi

  NEUROPHARMACOLOGY PERGAMON-ELSEVIER SCIENCE LTD 51 (2) 182 - 190 0028-3908 2006/08 [Refereed]
   

  Bisphosphonates, pyrophosphate analogues, known as inhibitors of bone resorption, appear to cause analgesia in certain clinical painful situations. To detect clinically relevant analgesic property of etidronate, a non-aminobisphosphonate, we examined and characterized its antiallodynic effect in the rat with adjuvant-induced arthritis, in comparison with alendronate, an aminobisphosphonate, as determined by the von Frey test. Repeated systemic administration of etidronate at 10-40 mg/kg/day suppressed the adjuvant-induced mechanical allodynia in rat hindpaw, an effect reaching a plateau in approximately 10 days. Systemic or intraplantar (i.pl.) administration of ATP-sensitive K+ (K-ATP(+)) channel inhibitors, glibenclamide and/or tolbutamide, completely reversed the antiallodynic effect of etidronate within 1 h in the arthritic rats, without affecting the nociceptive scores in naive or arthritic animals that had not received etidronate. Alendronate, administered repeatedly, also revealed similar glibenclamide-reversible antiallodynic effect. In contrast, the antiallodynic effect of repeated systemic indomethacin was resistant to i.pl. glibenclamide in the arthritic rats. Repeated administration of etidronate or alendronate only slightly attenuated the adjuvant-evoked hindpaw edema. Among K-ATP(+) channel subunits, mRNAs for Kir6.1, SUR1, SUR2A and SUR2B were abundant in rat dorsal root ganglia, while Kir6.2 mRNA was poor. Our data demonstrate that repeated etidronate as well as alendronate exhibits antiallodynic activity in arthritic rats, which might be clinically relevant, and suggest involvement of K-ATP(+) channels in the underlying mechanisms. (c) 2006 Elsevier Ltd. All rights reserved.
• Suppression of pancreatitis-related allodynia/hyperalgesia by proteinase-activated receptor-2 in mice

  A Kawabata; M Matsunami; M Tsutsumi; T Ishiki; O Fukushima; F Sekiguchi; N Kawao; T Minami; T Kanke; N Saito

  BRITISH JOURNAL OF PHARMACOLOGY NATURE PUBLISHING GROUP 148 (1) 54 - 60 0007-1188 2006/05 [Refereed]
   

  1 Proteinase-activated receptor-2 (PAR2), a receptor activated by trypsin and tryptase, is abundantly expressed in the gastrointestinal tract including the C-fiber terminal, and might play a role in processing of visceral pain. In the present study, we examined and characterized the roles of PAR2 in pancreatitis-related abdominal hyperalgesia/allodynia in mice. 2 Caerulein, administered i.p. once, caused a small increase in abdominal sensitivity to stimulation with von Frey hairs, without causing pancreatitis, in PAR2-knockout (KO) mice, but not wild-type (WT) mice. 3 Caerulein, given hourly six times in total, caused more profound abdominal hyperalgesia/allodynia in PAR2-KO mice, as compared with WT mice, although no significant differences were detected in the severity of pancreatitis between the KO and WT animals. 4 The PAR2-activating peptide, 2-furoyl-LIGRL-NH2, coadministered repeatedly with caerulein six times in total, abolished the caerulein-evoked abdominal hyperalgesia/allodynia in WT, but not PAR2-KO, mice. Repeated doses of 2-furoyl-LIGRL-NH2 moderately attenuated the severity of caerulein-induced pancreatitis in WT animals. 5 Our data from experiments using PAR2-KO mice provide evidence that PAR2 functions to attenuate pancreatitis-related abdominal hyperalgesia/allodynia without affecting pancreatitis itself, although the PAR2AP applied exogenously is not only antinociceptive but also anti-inflammatory.
• Mechanisms for modulation of mouse gastrointestinal motility by proteinase-activated receptor (PAR)-1 and-2 in vitro

  F Sekiguchi; N Hasegawa; K Inoshita; D Yonezawa; N Inoi; T Kanke; N Saito; A Kawabata

  LIFE SCIENCES PERGAMON-ELSEVIER SCIENCE LTD 78 (9) 950 - 957 0024-3205 2006/01 [Refereed]
   

  Proteinase-activated receptor (PAR)-1 or -2 modulates gastrointestinal transit in vivo. To clarify the underlying mechanisms, we characterized contraction/relaxation caused by TFLLR-NH2 and SLIGRL-NH2, PAR-1- and -2-activating peptides, respectively, in gastric and small intestinal (duodenal, jejunal and ileal) smooth muscle isolated from wild-type and PAR-2-knockout mice. Either SLIGRL-NH2 or TFLLR-NH2 caused both relaxation and contraction in the gastrointestinal preparations from wild-type animals. Apamin, a K+ channel inhibitor, tended to enhance the peptide-evoked contraction in some of the gastrointestinal preparations, whereas it inhibited relaxation responses to either peptide completely in the stomach, but only partially in the small intestine. Indomethacin reduced the contraction caused by SLIGRL-NH2 or TFLLR-NH2 in both gastric and ileal preparations, but unaffected apamin-insensitive relaxant effect of either peptide in ileal preparations. Repeated treatment with capsaicin suppressed the contractile effect of either peptide in the stomach, but not clearly in the ileum, whereas it enhanced the apamin-insensitive relaxant effect in ileal preparations. In any gastrointestinal preparations from PAR-2-knockout mice, SLIGRL-NH2, produced no responses. Thus, the inhibitory component in tension modulation by PAR-1 and -2 involves both apamin-sensitive and -insensitive mechanisms in the small intestine, but is predominantly attributable to the former mechanism in the stomach. The excitatory component in the PAR-1 and -2 modulation may be mediated, in part, by activation of capsaicin-sensitive sensory nerves and/or endogenous prostaglandin formation. Our study thus clarifies the multiple mechanisms for gastrointestinal motility modulation by PAR-1 and -2, and also provides ultimate evidence for involvement of PAR-2. (c) 2005 Elsevier Inc. All rights reserved.
• Signal transduction for proteinase-activated receptor-2-triggered prostaglandin E-2 formation in human lung epithelial cells

  N Kawao; M Nagataki; K Nagasawa; S Kubo; K Cushing; T Wada; F Sekiguchi; S Ichida; MD Hollenberg; WK MacNaughton; H Nishikawa; A Kawabata

  JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS 315 (2) 576 - 589 0022-3565 2005/11 [Refereed]
   

  We investigated proteinase-activated receptor-2 (PAR(2))-triggered signal transduction pathways causing increased prostaglandin E-2 (PGE(2)) formation in human lung-derived A549 epithelial cells. The PAR(2) agonist, SLIGRL-NH2 (Ser-Leu-Ile-Gly-Arg-Leu-amide), evoked immediate cytosolic Ca2+ mobilization and delayed (0.5-3 h) PGE(2) formation. The PAR(2)-triggered PGE(2) formation was attenuated by inhibition of the following signal pathway enzymes: cyclooxygenases 1 and 2 (COX-1 and COX-2, respectively), cytosolic Ca2+-dependent phospholipase A(2) (cPLA(2)), the mitogenactivated protein kinases (MAPKs), mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) and p38 MAPK, Src family tyrosine kinase, epidermal growth factor (EGF) receptor tyrosine kinase (EGFRK), and protein kinase C (PKC), but not by inhibition of matrix metalloproteinases. SLIGRL-NH2 caused prompt ( 5 min) and transient ERK phosphorylation, blocked in part by inhibitors of PKC and tyrosine kinases but not by an EGFRK inhibitor. SLIGRL-NH2 2 also evoked a relatively delayed (15 min) and persistent (30 min) phosphorylation of p38 MAPK, blocked by inhibitors of Src and EGFRK but not by inhibitors of COX-1 or COX-2. SLIGRL-NH2 elicited a Src inhibitor-blocked prompt (5 min) and transient phosphorylation of the EGFRK. SLIGRL-NH2 up-regulated COX-2 protein and/or mRNA levels that were blocked by inhibition of p38 MAPK, EGFRK, Src, and COX-2 but not MEK-ERK. SLIGRL-NH2 also caused COX-1-dependent up-regulation of microsomal PGE synthase-1 (mPGES-1). We conclude that PAR(2)-triggered PGE(2) formation in A549 cells involves a coordinated up-regulation of COX-2 and mPGES-1 involving cPLA(2), increased cytosolic Ca2+, PKC, Src, MEK-ERK, p38 MAPK, Src-mediated EGF receptor trans-activation, and also metabolic products of both COX-1 and COX-2.
• Development of agonists/antagonists for protease-activated receptors (PARs) and the possible therapeutic application to gastrointestinal diseases

  F Sekiguchi

  YAKUGAKU ZASSHI-JOURNAL OF THE PHARMACEUTICAL SOCIETY OF JAPAN PHARMACEUTICAL SOC JAPAN 125 (6) 491 - 498 0031-6903 2005/06 [Refereed][Invited]
   

  Protease-activated receptors (PARs), a family of G-protein-coupled seven-transmembrane-domain receptors, are activated by proteolytic unmasking of the N-terminal cryptic tethered ligand by certain serine proteases. Among four PAR family members cloned to date, PAR-1, PAR-2, and PAR-4 can also be activated through a non-enzymatic mechanism, which is achieved by direct binding of exogenously applied synthetic peptides based on the tethered ligand sequence, known as PARs-activating peptides, to the body of the receptor. Various peptide mimetics have been synthesized as agonists for PARs with improved potency, selectivity, and stability. Some peptide mimetics and/or nonpeptide compounds have also been developed as antagonists for PAR-1 and PAR-4. PARs are widely distributed in the mammalian body, especially throughout the alimentary systems, and play various roles in physiological/pathophysiological conditions, i.e., modulation of salivary, gastric, or pancreatic glandular exocrine secretion, gastrointestinal smooth muscle motility, gastric mucosal cytoprotection, suppression/facilitation of visceral pain and inflammation, etc. Thus PARs are now, considered novel therapeutic targets, and development of selective agonists and/or antagonists for PARs might provide a novel strategy for the treatment of various diseases that are resistant to current therapeutics.
• 2-Furoyl-LIGRL-NH2, a potent agonist for proteinase-activated receptor-2, as a gastric mucosal cytoprotective agent in mice

  A Kawabata; Y Oono; D Yonezawa; K Hiramatsu; N Inoi; F Sekiguchi; M Honjo; M Hirofuchi; T Kanke; H Ishiwata

  BRITISH JOURNAL OF PHARMACOLOGY NATURE PUBLISHING GROUP 144 (2) 212 - 219 0007-1188 2005/01 [Refereed]
   

  1 Proteinase-activated receptor-2 (PAR(2)), expressed in capsaicin-sensitive sensory neurons, plays a protective role in gastric mucosa. The present study evaluated gastric mucosal cytoprotective effect of 2-furoyl-LIGRL-NH2, a novel highly potent PAR(2) agonist, in ddY mice and in wild-type and PAR(2)-knockout mice of C57BL/6 background. 2 Gastric mucosal injury was created by oral administration of HCl/ethanol solution in the mice. The native PAR(2)-activating peptide SLIGRL-NH2, administered intraperitoneally (i.p.) at 0.3 - 1 mumol kg(-1) in combination with amastatin, an aminopeptidase inhibitor, but not alone, revealed gastric mucosal protection in ddY mice, which was abolished by ablation of capsaicin-sensitive sensory neurons. 3 I.p. administration of 2-furoyl-LIGRL-NH2 at 0.1 mumol kg(-1), without combined treatment with amastatin, exhibited gastric mucosal cytoprotective activity in ddY mice, the potency being much greater than SLIGRL-NH2 in combination with amastatin. This effect was also inhibited by capsaicin pretreatment. 4 Oral administration of 2-furoyl-LIGRL-NH2 at 0.003 - 0.03 mumol kg(-1) also protected against gastric mucosal lesion in a capsaicin-reversible manner in ddY mice. 5 I.p. 2-furoyl-LIGRL-NH2 at 0.1 - 0.3 mumol kg(-1) caused prompt salivation in anesthetized mice, whereas its oral administration at 0.003 - 1 mumol kg(-1) was incapable of eliciting salivation. 6 In wild-type, but not PAR(2)-knockout, mice of C57BL/6 background, i.p. administration of 2-furoyl-LIGRL-NH2 caused gastric mucosal protection. 7 Thus, 2-furoyl-LIGRL-NH2 is considered a potent and orally available gastric mucosal protective agent. Our data also substantiate a role for PAR2 in gastric mucosal protection and the selective nature of 2-furoyl-LIGRL-NH2.
• Effect of a potent iNOS inhibitor (ONO-1714) on acetaminophen-induced hepatotoxicity in the rat

  Y Kamanaka; A Kawabata; H Matsuya; C Taga; F Sekiguchi; N Kawao

  LIFE SCIENCES PERGAMON-ELSEVIER SCIENCE LTD 74 (6) 793 - 802 0024-3205 2003/12 

  Overproduction of nitric oxide (NO) in the liver has been implicated as an important event in endotoxin shock and in other models of hepatic inflammation and injury. The present study was undertaken to evaluate the effect of ONO-1714, a potent and specific inhibitor of inducible NO synthase (iNOS), on acetaminophen-induced hepatotoxicity in the rats. Oral administration of ONO-1714 dose-dependently inhibited NOx (NO2 and NO3-) accumulation in rat plasma after lipopolysaccharide (LPS) treatment. Intraperitoneal acetaminophen at 1 g/kg caused damage to the centrilobular regions of the liver and increase in serum alanine and aspartate transaminase (ALT and AST, respectively) levels accompanied by elevated plasma NOx levels after 24 h. Oral administration of ONO-1714 at 10 and 100 mug/kg dose-dependently reduced the acetaminophen-induced hepatic tissue damage and the increases in serum ALT and AST levels. ONO-1714 also blocked the increase in plasma NOx concentrations. These findings demonstrate that oral ONO-1714, an iNOS inhibitor, protects against acetaminophen-evoked hepatic inflammation/injury, strongly suggesting that NO produced by iNOS plays a key role in the pathogenesis of this drug-induced hepatotoxicity. (C) 2003 Elsevier Inc. All rights reserved.
• Symposium for Smooth Muscle and Vascular Endothelium

  Fumiko Sekiguchi

  Journal of Smooth Muscle Research 39 (6) 229  0916-8737 2003/12 [Refereed]
  
• The PAR-1-activating peptide facilitates pepsinogen secretion in rats

  N Kawao; K Hiramatsu; N Inoi; R Kuroda; H Nishikawa; F Sekiguchi; A Kawabata

  PEPTIDES ELSEVIER SCIENCE INC 24 (9) 1449 - 1451 0196-9781 2003/09 

  Protease-activated receptor-2 (PAR-2) is abundantly expressed in gastric mucosal chief cells, facilitating pepsinogen secretion. In the present study, we investigated whether PAR-1, a thrombin receptor, could modulate pepsinogen secretion in rats. The PAR-1-activating peptide TFLLR-NH2 as well as the PAR-2-activating peptide SLIGRL-NH2, administered i.v. repeatedly at 1-h intervals, significantly increased gastric pepsinogen secretion over 2-4 h (after two to four doses). In contrast, the control peptide FTLLR-NH2, given in the same manner, had no such effect. Thus, PAR-1, like PAR-2, might function to facilitate pepsinogen secretion, suggesting a novel role of the thrombin-PAR-1-pathway in the stomach. (C) 2003 Elsevier Inc. All rights reserved.
• Gastric relaxation by inhibitory neurotransmitters in hypertensive rats

  SHIMAMURA Keiichi; KIMURA S; SEKIGUCHI Fumiko; SUNANO Satoru; SAITO H

  Biomed. Res. 14 (1) 62 - 69 2003/04 [Refereed]
   

  高血圧ラット（SHRSP）と正常血圧ラット（WKY）の胃底部における一酸化窒素（NO）神経性弛緩反応を比較したところ、SHRSP、WKY 標本間でほとんど差がないことが明らかとなった。（英文）
• Effects of L-arginine on spontaneous contraction of the rat portal vein

  K Shimamura; M Zhou; M Toba; S Kimura; T Higuchi; H Kawaguchi; F Sekiguchi; S Sunano

  PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY SPRINGER-VERLAG 446 (1) 30 - 35 0031-6768 2003/04 [Refereed]
   

  The effects Of L-arginine on spontaneous contraction of endothelium-denuded longitudinal preparations of the rat portal vein were studied. L-Arginine increased the frequency of spontaneous contraction concentration-dependently between 10 muM and 1 mM. Changes in contraction amplitude and duration were not remarkable. D-Arginine had a negligible effect on spontaneous contraction. N-omega-nitro-L-arginine (1 mM) did not affect spontaneous contraction or the response to L-arginine. Addition of N-G-monomethyl-L-arginine (1 mM), L-lysine (1 mM) or N-ethymaleimide (0.1 mM) increased the frequency of spontaneous contractions and inhibited the. effect Of L-arginine. Glibenclamide (10 muM) did not affect spontaneous contraction or the response to L-arginine. Spontaneous increase in concentration of intracellular Ca2+, estimated as the ratio of Fura-PE3 fluorescence occurred synchronously with spontaneous contraction. Spontaneous increase in concentration of intracellular Ca2+ occurred more frequently in the presence Of L-arginine (I MM). L-Arginine (1 mM) also increased the number of action potential bursts/min in the longitudinal smooth muscle layer. L-Arginine (I mM) also depolarized cell membranes. This study indicates that L-arginine increases the frequency of spontaneous contraction of longitudinal muscle in the rat portal vein by membrane depolarization through mechanisms that do not involve, nitric oxide or the inhibition of ATP-sensitive K+ channels.
• Caffeine-induced relaxation is unimpaired in the aorta of stroke-prone spontaneously hypertensive rats（SHRSP）

  Sekiguchi Fumiko; Miyake Yoshimasa; Sunano Satoru

  Bulletin of Pharmaceutical Research and Technology Institute Kinki University 11 131 - 142 0919-7567 2003/03 

  高血圧ラットの血管では内皮依存性弛緩反応の減少がみられるが、カフェインは内皮非依存性の弛緩を引き起こし、この弛緩反応は正常血圧と高血圧ラットの大動脈で差がなかったことから、平滑筋の反応性には異常がないことが示唆された。（英文）
• Caffeine-induced contracture in oesophageal striated muscle of normotensive and hypertensive rats

  F Sekiguchi; K Kawata; M Komori; S Sunano

  EUROPEAN JOURNAL OF PHARMACOLOGY ELSEVIER SCIENCE BV 465 (1-2) 153 - 161 0014-2999 2003/03 [Refereed]
   

  To elucidate whether properties of the sarcoplasmic reticulum are altered, not only in vascular smooth muscle, but also in visceral striated muscle of spontaneously hypertensive rats (SHR), caffeine-induced contractures in oesophageal striated muscle of Wistar Kyoto rats (WKY) and stroke-prone SHR (SHRSP) were compared. In both preparations, 30 mM caffeine induced a contracture with two components. The second component, which was diminished by extracellular Ca2+ removal or Ni2+ but not by verapamil, was much smaller in SHRSP. Both components and differences between WKY and SHRSP coincided with changes in intracellular Ca2+. Although membrane potential was identical between these preparations, caffeine induced slight depolarization only in WKY preparations. Similar depolarization was observed with 10 mM K+, which induced no contraction. It is suggested that the first and the second components of caffeine-induced contracture were induced by Ca2+ released from sarcoplasmic reticulum and by Ca2+ that entered through channels activated by sarcoplasmic reticulum Ca2+ depletion, respectively In SHRSP preparations, Ca2+ from the latter pathway was clearly decreased, although this change is thought not to be related to the initiation of hypertension. These results suggest that Ca2+ handling properties of cell membrane and sarcoplasmic reticulum are generally altered in muscles of SHRSP. (C) 2003 Elsevier Science B.V. All rights reserved.
• Endothelium-derived factors in hypertensive blood vessels, especially nitric oxide and hypertension

  Satoru Sunano; Fumiko Sekiguchi

  Yakugaku Zasshi Pharmaceutical Society of Japan 123 (7) 495 - 515 1347-5231 2003 [Invited]
   

  Endothelium-dependent relaxation (EDR) in the blood vessels of spontaneously hypertensive rats (SHR) and the role of nitric oxide (NO) in the initiation of hypertension are reviewed. EDR was impaired in blood vessels of SHR depending on age and degree of hypertension when compared with those of normotensive rats. The cause of the impairment varied among the type of blood vessels: a decrease in the production of NO and endothelium-derived relaxing factor (EDRF) and an increase in the production of endothelium-derived contracting factor (EDCF) are the main causes of the impairment in large arteries, while a decrease in endothelium-dependent hyperpolarization and increased release of EDCF are the main causes of the impairment in small arteries. Interactions among these endothelium-derived factors and changes in the interactions are also causes of impairment. Superoxide may be involved in the impairment of EDR by destroying NO. The endothelium depresses smooth muscle contraction, including spontaneous tone developed in vascular smooth muscle, and the depressing effect of the endothelium is impaired in the preparations from SHR. The endothelium of blood vessels of SHR are structurally injured as demonstrated by scanning electron microscopy. Antihypertensive treatment prevented these functional and structural changes. Chronic treatment with inhibitors of NO production in normotensive rats impaired EDR and elevated blood pressure. The impairment of EDR is a secondary change due to continued hypertension, and early initiation of antihypertensive therapy is recommended. © 2003 The Pharmaceutical Society of Japan.
• Effects of drugs which act on the sarcoplasmic reticulum in the esophageal striated muscles from normotensive and spontaneously hypertensive rats

  関口 富美子; 砂野 哲

  Journal of Muscle Research and Cell Motility 23 (4・5) 131 - 144 2002/12 

  ラット食道横紋筋では筋小胞体作用薬により細胞外カルシウム流入が引き起こされ、この流入は正常血圧ラットに比べ高血圧ラット標本において減少していることが示唆された。（英文）
• Hypertension and impairment of endothelium dependent relaxation of arteries from spontaneously hypertensive and L NAME treated Wistar rats

  関口 富美子; 砂野 哲

  薬学合研究所紀要 (10) 33 - 45 2002/03 

  Wistar ラットに L ニトロアルギニン （L NAME） を長期経口投与すると血圧が上昇した。 そのラット動脈の内皮依存性弛緩は非投与ラットに比べ著明に減弱していた。 この減弱は標本に残存した L NAME によるもので投薬による血圧上昇は関与していないと示唆された。 （英文）
• Arterial smooth muscle tone and its modification by endothelium in spontaneously hypertensive rats.

  SUNANO Satoru; SEKIGUCHI Fumiko; SHIMAMURA Keiichi

  Biomed. Res. 11 137 - 147 2000 [Refereed][Invited]
  
• Tension oscillation in arteries and its abnormality in hypertensive animals

  K Shimamura; F Sekiguchi; S Sunano

  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY BLACKWELL SCIENCE ASIA 26 (4) 275 - 284 0305-1870 1999/04 [Invited]
   

  1. The mechanisms of oscillatory contraction of arterial smooth muscle in vitro are discussed. 2. The membrane potential and cytoplasmic free Ca2+ concentration in smooth muscle cells oscillate in the presence of agonists. 3. The oscillatory change in the membrane potential of smooth muscle cells is related to Ca2+ release from intracellular stores. 4. Gap junctions between smooth muscle cells play important roles in the synchronized oscillation of the cytoplasmic free Ca2+ concentration in this population of cells. 5. Endothelial cells may increase or decrease the tension oscillation of smooth muscle cells. 6. In arteries from hypertensive rats, an increase in membrane excitability and the number of gap junctions between smooth muscle cells and impaired endothelial function are the main factors responsible for the modulation of tension oscillation.
• Abnormality of the endothelium-dependent and -independent tension oscillation in the artery of spontaneously hypertensive rats.

  SHIMAMURA Keiichi; SEKIGUCHI Fumiko; SUNANO Satoru

  J. Smooth Muscle Res. (Japanese Section), 2 J-99 - J116 1999 [Invited]
  
• Abnormality of hyperpolarization and relaxation mediated by the endothelium-derived factors in spontaneously hypertensive rats

  SUNANO Satoru; SEKIGUCHI Fumiko; MATSUDA Kyoko; SHIMAMURA Keiichi

  J. Smooth Muscle Res. (Japanese Section), Japan Society of Smooth Muscle Research 1 (3) J-101 - J-116 1342-8152 1997 [Invited]
   

  The membrane hyperpolarization produced by endothelium-derived hyperpolarizing factor (EDHF) is one of the components in the endothelium-dependent relaxations. Different subtype of endothelium receptor is involved in the release of EDHF from that for nitric oxide. Although EDHF has not been identified, it may be related to cytochrome P450. The responses mediated by EDHF have been studied by observation of membrane potential or relaxation which is resistant to inhibitors of nitric oxide synthase and cyclooxygenase. The responses are dependent on potassium gradient across cell membrane, therefore, the response is mediated by potassium channels. The EDHF-mediated hyperpolarization or relaxation is sensitive to charybdotoxin plus apamin, inhibitors of calcium activated potassium channels. The EDHF-mediated response is more remarkable in small resistant arteries than large arteries, therefore, EDHF may play an important role in the regulation of vascular resistance. The EDHF-mediated response is decreased in hypertensive or aged animals. Understanding of EDHF-mediated response will promote development of a new strategy for the treatment of pathophysiological conditions.
• Effects of cyclopiazonic acid and thapsigargin on electromechanical activities and intracellular Ca2+ in smooth muscle of carotid artery of hypertensive rats

  F Sekiguchi; K Shimamura; M Akashi; S Sunano

  BRITISH JOURNAL OF PHARMACOLOGY STOCKTON PRESS 118 (4) 857 - 864 0007-1188 1996/06 [Refereed]
   

  1 The effects of cyclopiazonic acid (CPA) and thapsigargin (TG), both of which are known to inhibit sarcoplasmic reticular Ca2+-ATPase, on the mechanical activities, intracellular Ca2+ level and electrical activities of smooth muscle of the carotid artery of stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar Kyoto rats (WKY) were compared. 2 Both CPA and TG induced elevation of tension of the smooth muscle, which was composed of a phasic and a tonic component. The level of tension attained, especially the tonic component, was greater in the preparation from SHRSP. 3 The elevation of tension was associated with an increased intracellular Ca2+ level. Both the elevation of tension and the increase in intracellular Ca2+ were diminished by the removal of extracellular Ca2+ or by the application of verapamil. 4 The resting membrane potential of the preparations from SHRSP were depolarized to a greater extent than those from WKY. CPA depolarized the smooth muscle from both SHRSP and WKY, and the final level was also more depolarized in the preparation from SHRSP. 5 These results indicate that the elevation of tension induced by these drugs is mainly due to increased Ca2+ influx through voltage-dependent Ca2+ channels, and the difference in the action between the preparation from SHRSP and that from WKY can be explained mainly by the changes in the channels. 6 Thus, differences in the action of these drugs on the tension of smooth muscle between preparations from WKY and SHRSP can mainly be explained by the difference in the membrane potential which is related to the difference in voltage-dependent Ca2+ influx.
• Spontaneous and agonist-induced contractions and endothelium-dependent relaxation in aortae from SHRSP and WKY rats under various levels of passive force

  F Sekiguchi; T Adachi; H Matsubara; K Matsuda; K Kita; K Shimamura; S Sunano

  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY WILEY 23 (6-7) 483 - 489 1440-1681 1996/06 [Refereed]
   

  1. The influence of the passive force on the contraction and endothelium-dependent relaxation in aortae of normotensive Wister Kyoto (WKY) rats and stroke-prone spontaneously hypertensive rats (SHRSP) Here compared. 2. Force changes of endothelium-intact and -removed preparations were measured isometrically by a force-displacement transducer, Endothelium-dependent relaxation was observed by applying acetylcholine to the preparation precontracted in the presence of 5 x 10(-7) mol/L noradrenaline. 3. The preparations showed spontaneously developed tension (tone) that increased with the increase in the passive force. The effect of passive force was greater in preparations from SHRSP. Contraction initiated by noradrenaline was also increased by passive force up to 30 mN, then showed a tendency to decrease. 4. Endothelium-dependent relaxation was depressed as the passive force was increased. Preparations from SHRSP showed impaired endothelium-dependent relaxation and were influenced by passive force to a lesser degree when compared with preparations from WKY rats. 5. Relaxation by sodium nitroprusside was influenced by passive force to a much lesser extent than that by acetylcholine. 6. Indomethacin potentiated endothelium-dependent relaxation and blocked the effect of passive force in both preparations. 7. The difference in relaxation and the effect of passive force is primarily caused by the difference in the release of endothelium-derived contracting factor, which is thought to be a product of the cyclo-oxygenase pathway of the arachidonic acid cascade.
• Endothelium-Dependent relaxation by alpha(2)-adrenoceptor agonists in spontaneously hypertensive rat aorta

  S Sunano; LB Zou; K Matsuda; F Sekiguchi; H Watanabe; K Shimamura

  JOURNAL OF CARDIOVASCULAR PHARMACOLOGY LIPPINCOTT-RAVEN PUBL 27 (5) 733 - 739 0160-2446 1996/05 [Refereed]
   

  Differences in alpha(2)-adrenoceptor-induced relaxation of the aorta between stroke-prone spontaneously hypertensive rats (SHRSP) and control normotensive Wistar Kyoto rats (WKY) were studied. Changes in the tension of ring preparations of the aortas were measured isometrically. Relaxation was observed in the preparations precontracted in the presence of ONO-11113. a thromboxane A(2) analogue. The alpha(2)-agonist clonidine and UK-14304 induced dose-dependent relaxation in both the WKY and HRP preparations. The relaxation was impaired in the SHRSP preparation. A modified sandwich experiment showed that the relaxing substance from the SHRSP endothelium was decreased. Acetylcholine (ACh) also induced dose-dependent relaxation, and the relaxation was impaired in the SHRSP preparations. alpha(2)-Agonists induced a greater degree of impairment in the relaxation than did ACh. The relaxation induced by alpha(2)-agonists and by ACh was blocked by N-G-nitro-L-arginine (L-NNA). Indomethacin improved the relaxation induced by ACh but not that induced by alpha(2)-agonisrs in the SHRSP aortas. These results suggest that the impairment of relaxation by alpha(2)-agonists in SHRSP is not caused by the increase in the release of endothelium-derived contracting factor (EDCF) but by the reduction in the release of nitric oxide (NO). Alteration of the alpha(2)-adrenoceptors and/or the intracellular mechanism through which NO is synthesized by stimulation of the alpha(2)-adrenoceptors may be the cause of the reduction in relaxation.
• Blood pressure and age-dependent changes of endothelium-dependent tension oscillations in different strains of spontaneously hypertensive rats

  K. Shimamura; K. Matsuda; F. Sekiguchi; S. Sunano

  Journal of Smooth Muscle Research Japan Society of Smooth Muscle Research 32 (4) 145 - 154 0916-8737 1996 [Refereed]
   

  The influences of blood pressure and age of spontaneously hypertensive rats on endothelium dependent tension oscillation of aortic preparation were studied. Rats with different blood pressures, normotensive Wistar Kyoto rats (WKY), spontaneously hypertensive rats (SHR), stroke prone ShR (SHRSP) and malignant type of SHRSP (M SHRSP), were used. The effects of antihypertensive treatment of SHRSP on the tension oscillation were also studied. High doses of noradrenaline induced tension oscillations in endothelium intact preparations of all strains of young rats. The rate of the occurrence of the tension oscillation decreased age dependently. The decrease was faster when the blood pressure of the rats was higher Application of acetylcholine in the presence of noradrenaline induced a relaxation and tension oscillations, both of which were negatively dependent on age anti blood pressure. Antihypertensive treatment of hypertensive rats with hydralazine or captopril prevented a decrease in incidence of the tension oscillation. These influences of age and blood pressure as well as antihypertensive treatments on the tension oscillation resembled those on the endothelium dependent relaxation and are thought to be brought about by functional changes of the endothelium.
• Neural responses of rat abdominal skin artery.

  Shimamura, K; Akagi, K; Yamamoto, K; Sekiguchi, F; Sunano, S

  J. Smooth Muscle Res. 31 397 - 399 1995/12 [Refereed]
  
• Effects of N(G)-nitro-L-arginine on α-agonists induced contraction of aortae from Wistar Kyoto rats and stroke-prone spontaneously hypertensive rats

  K. Matsuda; F. Sekiguchi; M. Tojo; K. Shimamura; S. Sunano

  Journal of Smooth Muscle Research Japan Society of Smooth Muscle Research 31 (2) 51 - 60 0916-8737 1995 [Refereed]
   

  Differences in the influences of endothelium derived nitric oxside (NO) on α-agonists-induced contraction in the aortae of spontaneously hypertensive and normotensive rats were studied by blocking NO synthesis with N(G)-nitro- L-arginine (L-NNA). L-NNA potentiated the contraction induced by noradrenaline. The potentiation was smaller in the preparation from stroke prone spontaneously hypertensive rats (SHRSP) than in the preparation from Wistar Kyoto rats (WKY). Similar potentiation was observed in the contraction induced by phenylephrine the potentiation was also smaller in the preparation from SHRSP. α2-agonists, clonidine and UK-14304 induced dose dependent contraction only in the presence of L-NNA. The dose response curves for α2-agonists in SHRSP aorta were different from those in WKY aorta the maximum tension was observed at the concentration of 10-6 M in the preparation from WKY, while the contraction further increased up to 10-4 M in the preparation from WKY. Noradrenaline, clonidine and UK-14304 but not phenyrephrine induced relaxation which was blocked by L-NNA. The relaxation was impaired in the preparation from SHRSP in greater extent than that by acetylcholine. It is suggested that basic or noradrenaline-stimulated NO release from endothelium decreased in the preparation from SHRSP and that α2-adrenoceptor of both the endothelium and smooth muscle may be altered in the preparation from SHRSP.
• Comparison of endothelium-dependent and -independent tension oscillation in aortae of stroke-prone spontaneously hypertensive rats and Wistar Kyoto rats

  S. Sunano; F. Sasaki; S. Osugi; K. Shimamura

  Journal of Smooth Muscle Research Japan Society of Smooth Muscle Research 30 (4) 135 - 145 0916-8737 1994 [Refereed]
   

  Differences in noradrenaline-induced tension oscillations between aortae from stroke-prone spontaneously hypertensive rats (SHRSP) and normotensive control Wistar Kyoto rats (WKY) were studied. Endothelium-intact and -removed ring preparations were made from thoracic aorta of SHRSP and WKY, and isometric contraction was observed. Endothelium-intact preparations from WKY showed tension oscillations in response to high concentration of noradrenaline at significantly higher ratio, while only a few endothelium-removed preparation showed tension oscillations in response to low concentration of the drug. Fifteen out of 41 endothelium-removed preparations from SHRSP showed tension oscillations in response to low concentration of noradrenaline but no preparation showed oscillations in response to high concentration of the drug. Seven and 14 out of 42 endothelium-intact preparations from SHRSP showed oscillatory response to low and high concentration of the drug respectively. Acetylcholine-induced relaxation and tension oscillations, both of which being significantly less in the preparation from SHRSP. Both the endothelium-independent tension oscillations and endothelium-dependent tension oscillations were abolished by removal of extracellular Ca or by verapamil. It is suggested that aortic smooth muscle of SHRSP possesses the property which produced tension oscillations, while the tension oscillations of WKY aorta is endothelium-dependent. The opening of voltage-dependent Ca++ channel of smooth muscle cell membrane which generates rhythmic contraction is increased in the aorta of SHRSP, while the release of endothelium-derived factors which induces rhythmic activities of smooth muscle cell is decreased.
• THE PRESENCE OF LOW-MOLECULAR-WEIGHT GERMINATIVE SUBSTANCES IN BACILLUS-CEREUS T-SPORE EXTRACT

  H SHIBATA; Y ODAHARA; F SASAKI; O HIROTA; M NISHIDA; TANI, I

  MICROBIOLOGY AND IMMUNOLOGY CENTER ACADEMIC PUBL JAPAN 38 (7) 519 - 525 0385-5600 1994 [Refereed]
   

  An extract from intact spores of Bacillus cereus T having a germination-inducing activity was studied. Two distinct germinative principles were found through dialysis of the extract. One was diffusible through the dialysis membrane and the other was non-diffusible. The activity of the former fraction was inhibited by the addition of 1 mM glyeoletherdiamine-N,N,N',N'-tetraacetic acid (GEDTA), whereas the latter fraction was inactive unless GEDTA was added to the assay system. The diffusible principle maintained the major portion of the activity found in the crude spore extract. By means of high-performance liquid chromatography (HPLC) using a gel permeation chromatography column, 9 fractions were obtained from the deproteinized diffusible fraction. Of those fractions, two fractions (No. 1 and No. 8) were responsible for the germination-inducing activity, but no reconstituted activity was observed unless both fractions No. 1 and No. 8 were added to the assay system. Amino acid analysis of fraction No. 1 revealed that the fraction was rich in free amino acids, especially in alanine. On the other hand, by the use of reverse-phase HPLC and fast atom bombardment mass spectrometry, it was concluded that the effective substance in fraction No. 8 was inosine. Based on these findings, it was suggested that the active substances in fraction No. I might be a free amino acid such as L-alanine and/or Ca2+ and a Ca2+-binding substance.
• Relationship between blood pressure and smooth muscle tone in aortae of hypertensive rats: Roles of (Ca2+)

  Fumiko Sasaki; S. Osugi; K. Shimamura; S. Sunano

  Journal of Smooth Muscle Research 29 (3) 69 - 79 1884-8796 1993 [Refereed]
   

  Spontaneously developed tension (active tone) and intracellular Ca2+ level of aortae from spontaneously hypertensive rats (SHR), stroke-prone SHR (SHRSP), malignant SHRSP (M-SHRSP) and control Wistar Kyoto rats (WKY) were compared. Systolic blood pressure of WKY, SHR, SHRSP and M-SHRSP was 130mmHg, 200mmHg, 250mmHg and 260mmHg, respectively. Preparations from all strains of spontaneously hypertensive rats exhibited active tone which was abolished by the removal of extracellular Ca2+ or by the application of verapamil. The active tone was greater in the order of aortae from SHR< SHRSP< M-SHRSP. Intracellular Ca2+ level measured by Fura-2 method decreased by the removal of extracellular Ca2+. The degree of the decrease was greater as the blood pressure of the rats increased, indicating the greater elevation of intracellular Ca2+level in the presence of extracellular Ca2+. A correlation was obtained between the active tone, intracellular Ca2+level and blood pressure. Thus, it was demonstrated that the development of the active tone is brought about by the changes in Ca2+ influx of smooth muscle cell membrane and the degree of the change is positively related to the degree of hypertension. © 1993, Japan Society of Smooth Muscle Research. All rights reserved.
• Elevation of spontaneous tone and effects of antihypertensive treatments in arterial smooth muscle of spontaneously hypertensive rats

  S. Sunano; F. Sasaki

  Journal of Smooth Muscle Research Japan Society of Smooth Muscle Research 29 (4) 111 - 130 0916-8737 1993 [Invited]
   

  Mechanisms of elevation of active tone in arterial smooth muscle of spontaneously hypertensive rats and effects of antihypertensive treatments are reviewed. Spontaneously hypertensive rats are created by Okamoto et al. and classified mainly into three strains, SHR, SHRSP and M-SHRSP. Blood pressure of the rats is higher in this order. The aortic smooth muscle of these rats exhibits elevation of the active tension (tone) under nonstimulated condition. The active tone is greater as the blood pressure of the rats elevated and good correlation between blood pressure and active tone can be obtained. The active tone is sensitive to extracellular Ca and abolished by the removal of extracellular Ca or by the application of Ca-antagonists. It is also associated with increased intracellular Ca level. These results indicate that the active tone is brought about by increase in voltage-dependent Ca channel opening of the cell membrane. Increased voltage-dependent Ca channel opening, i.e. membrane depolarization and increased inward Ca current can be a cause of the elevated tone. Abnormalities in the cellular mechanisms for relaxation of the smooth muscle can also contribute to the elevation of the active tone. Endothelium suppresses the active tone, probably releasing endothelium-derived relaxing factor or hyperpolarizing factor. The suppression of contraction by endothelium is impaired in the blood vessels of spontaneously hypertensive rats, depending on the degree of hypertension. Antihypertensive treatments prevent the development or elevation of the active tone. It also prevents the impairment of function of endothelium. Thus, the maintained hypertension alters functions of smooth muscle membrane and endothelium. The degree and duration of hypertension are thought to be determinant factors of these abnormalities.
• 臨床を反映した動物モデルを用いた病態解明の最前線 急性膵炎・膵臓痛動物モデルを用いた病態解析 T型Ca2+チャネルおよびTRPチャネルの役割

  寺田 侑加; 坪田 真帆; 関口 富美子; 和田 恭一; 桑原 健; 高田 充隆; 川畑 篤史

  日本薬学会年会要旨集 (公社)日本薬学会 135年会 (1) 333 - 333 0918-9823 2015/03
• Cystitis-Related Bladder Pain Involves ATP-Dependent HMGB1 Release from Macrophages and Its Downstream H2S/Cav3.2 Signaling in Mice.

  Shiori Hiramoto; Maho Tsubota; Kaoru Yamaguchi; Kyoko Okazaki; Aya Sakaegi; Yuki Toriyama; Junichi Tanaka; Fumiko Sekiguchi; Hiroyasu Ishikura; Hidenori Wake; Masahiro Nishibori; Huy Du Nguyen; Takuya Okada; Naoki Toyooka; Atsufumi Kawabata

  Cells 9 (8) 2020/07 

  Cystitis-related bladder pain involves RAGE activation by HMGB1, and increased Cav3.2 T-type Ca2+ channel activity by H2S, generated by upregulated cystathionine-γ-lyase (CSE) in mice treated with cyclophosphamide (CPA). We, thus, investigated possible crosstalk between the HMGB1/RAGE and CSE/H2S/Cav3.2 pathways in the bladder pain development. Bladder pain (nociceptive behavior/referred hyperalgesia) and immuno-reactive CSE expression in the bladder were determined in CPA-treated female mice. Cell signaling was analyzed in urothelial T24 and macrophage-like RAW264.7 cells. The CPA-induced bladder pain was abolished by pharmacological inhibition of T-type Ca2+ channels or CSE, and genetic deletion of Cav3.2. The CPA-induced CSE upregulation, as well as bladder pain was prevented by HMGB1 inactivation, inhibition of HMGB1 release from macrophages, antagonists of RAGE or P2X4/P2X7 receptors, and N-acetylcysteine, an antioxidant. Acrolein, a metabolite of CPA, triggered ATP release from T24 cells. Adenosine triphosphate (ATP) stimulated cell migration via P2X7/P2X4, and caused HMGB1 release via P2X7 in RAW264.7 cells, which was dependent on p38MAPK/NF-κB signaling and reactive oxygen species (ROS) accumulation. Together, our data suggest that CPA, once metabolized to acrolein, causes urothelial ATP-mediated, redox-dependent HMGB1 release from macrophages, which in turn causes RAGE-mediated CSE upregulation and subsequent H2S-targeted Cav3.2-dependent nociceptor excitation, resulting in bladder pain.
• Spontaneous and agonist-induced contractions and endothelium-dependent relaxation in aortae from SHRSP and WKY rats under various levels of passive force

  Fumiko Sekiguchi; Tomoko Adachi; Hideki Matsubara; Kyoko Matsuda; Katsuhiro Kita; Keiichi Shimamura; Satoru Sunano

  Clinical and Experimental Pharmacology and Physiology Blackwell Publishing 23 (6-7) 483 - 489 0305-1870 1996 [Refereed]
   

  1. The influence of the passive force on the contraction and endothelium- dependent relaxation in aortae of normotensive Wistar Kyoto (WKY) rats and stroke-prone spontaneously hypertensive rats (SHRSP) were compared. 2. Force changes of endothelium-intact and -removed preparations were measured isometrically by a force-displacement transducer. Endothelium-dependent relaxation was observed by applying acetylcholine to the preparation precontracted in the presence of 5 x 10-7 mol/L noradrenaline. 3. The preparations showed spontaneously developed tension (tone) that increased with the increase in the passive force. The effect of passive force was greater in preparations from SHRSP. Contraction initiated by noradrenaline was also increased by passive force up to 30 mN, then showed a tendency to decrease. 4. Endothelium-dependent relaxation was depressed as the passive force was increased. Preparations from SHRSP showed impaired endothelium- dependent relaxation and were influenced by passive force to a lesser degree when compared with preparations from WKY rats. 5. Relaxation by sodium nitroprusside was influenced by passive force to a much lesser extent than that by acetylcholine. 6. Indomethacin potentiated endothelium-dependent relaxation and blocked the effect of passive force in both preparations. 7. The difference in relaxation and the effect of passive force is primarily caused by the difference in the release of endothelium-derived contracting factor, which is thought to be a product of the cyclo-oxygenase pathway of the arachidonic acid cascade.
• Effect of passive force on endothelium-dependent relaxation in aortae from Wistar Kyoto rats and stroke-prone spontaneously hypertensive rats.

  F Sekiguchi; K Yamamoto; K Shimamura; S Sunano

  JAPANESE HEART JOURNAL JAPAN HEART JOURNAL, SECOND DEPT OF INTERNAL MED 38 (4) 590 - 590 0021-4868 1997/07 [Refereed]
  
• Ca sensitivity of the contraction of portal vein circular muscle from hypertensive rats.

  LB Zou; K Shimamura; K Yamamoto; K Matsuda; F Sekiguchi; S Sunano

  JAPANESE HEART JOURNAL JAPAN HEART JOURNAL, SECOND DEPT OF INTERNAL MED 38 (4) 585 - 585 0021-4868 1997/07 [Refereed]
  
• Endothelium-dependent hyperpolarization in hypertensive rat mesenteric artery.

  K Shimamura; K Yamamoto; K Matsuda; LB Zou; F Sekiguchi; S Sunano

  JAPANESE HEART JOURNAL JAPAN HEART JOURNAL, SECOND DEPT OF INTERNAL MED 38 (4) 584 - 584 0021-4868 1997/07 [Refereed]
  
• H2S and smooth muscle motility

  Fumiko Sekiguchi; Satoko Kubo; Yuko Kurokawa; Hitomi Hayahi; Hiroyuki Nishikawa; Yukari Okamoto; Atsufumi Kawabata

  YAKUGAKU ZASSHI-JOURNAL OF THE PHARMACEUTICAL SOCIETY OF JAPAN PHARMACEUTICAL SOC JAPAN 127 89 - 92 0031-6903 2007 [Refereed]
   

  Hydrogen sulfide (H2S), the third gaseous mediator following nitric oxide (NO) and carbon monoxide, modulates various physiological functions in the mammalian body. Here we analyzed and characterized roles for H2S in modulation of smooth muscle motility. In precontracted aortic rings prepared from rats and mice, NaHS, a donor of H2S, induced contraction at low concentrations and relaxation at high concentrations. The NaHS-induced relaxation involved both ATP-sensitive K+ (KATP) channel-dependent and -independent pathways in rat aorta, but was independent of KATP channels in mouse aorta. The NaHS-induced contraction was attributable to direct inhibition of endothelial NO synthase by NaHS. NaHS at high concentrations also caused KATP channel-independent relaxation in airway and gastrointestinal smooth muscle preparations from rats, mice or guinea-pigs. Together, H2S modulates smooth muscle motility through multiple mechanisms, being excitative and suppressive.
• Reduced effect of caffeine on twitch contraction of oesophageal striated muscle from stroke-prone spontaneously hypertensive rats

  F Sekiguchi; K Kawata; K Shimamura; S Sunano

  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY BLACKWELL PUBLISHING ASIA 30 (4) 223 - 231 0305-1870 2003/04 [Refereed]
   

  1. There are known differences in the sensitivity to caffeine between skeletal muscle (soleus) of normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). The present study was performed in order to examine differences in the effects of caffeine on twitch contraction between visceral striated muscle using the outer layer of the oesophagus from WKY rats and stroke-prone SHR (SHRSP). 2. Caffeine, at concentrations ranging from 0.3 to 10 mmol/L, exhibited potentiating effects on twitch contraction in preparations from both WKY rats and SHRSP. The potentiating effect of caffeine was markedly less prominent in preparations from SHRSP compared with preparations from WKY rats. 3. The rate of contraction and relaxation, the time to peak tension and 80% relaxation time were not significantly altered by caffeine at concentrations lower than 3 mmol/L in preparations from either strain. 4. With 10 mmol/L caffeine, the rate of relaxation was markedly reduced and the 80% relaxation time was prolonged, with no significant changes in the rate of contraction, in preparations from WKY rats. These changes were significantly smaller in preparations from SHRSP. 5. The duration of the action potential was greater in preparations from SHRSP than in preparations from WKY rats, although the membrane potential and the amplitude of the action potential were not significantly different between preparations from WKY rats and SHRSP. 6. Caffeine, at 10 mmol/L, prolonged the duration of the action potential in preparations from both strains. The effect of caffeine was not different between preparations from WKY rats and SHRSP. 7. The results of the present study suggest that caffeine augments release of Ca2+ from the sarcoplasmic reticulum (SR) at low concentrations and attenuates Ca2+ re-uptake at 10 mmol/L. Decreased reactivity of SR to caffeine may be a cause of the lesser potentiation of twitch contraction by caffeine in preparations from SHRSP.
• Effect of chronic treatment with carvedilol on the membrane potential of mesenteric artery of spontaneously hypertensive rats.

  K Shimamura; K Yamamoto; F Sekiguchi; M Tanaka; S Sunano

  JAPANESE HEART JOURNAL JAPAN HEART JOURNAL, SECOND DEPT OF INTERNAL MED 39 (4) 548 - 548 0021-4868 1998/07 [Refereed]
  
• Comparison of the contractile response and intracellular Ca2+ level in esophageal striated muscle of Wistar Kyoto rats and stroke-prone spontaneously hypertensive rats.

  F Sekiguchi; K Yamamoto; K Shimamura; S Sunano

  JAPANESE HEART JOURNAL JAPAN HEART JOURNAL, SECOND DEPT OF INTERNAL MED 39 (4) 573 - 573 0021-4868 1998/07 [Refereed]
  
• Tacrolimus, a calcineurin inhibitor, promotes capsaicin-induced colonic pain in mice.

  Kazuki Matsui; Yuka Terada; Maho Tsubota; Fumiko Sekiguchi; Atsufumi Kawabata

  Journal of pharmacological sciences 143 (1) 60 - 63 2020/05 [Refereed]
   

  TRPV1 is phosphorylated and functionally upregulated by protein kinases, and negatively regulated by phosphatases including calcineurin. Since the clinical use of calcineurin-inhibiting immunosuppressants is commonly associated with chronic diarrhea, we examined if tacrolimus, a calcineurin inhibitor, promotes TRPV1-dependent colonic hypersensitivity in mice. Intracolonic administration of capsaicin, a TRPV1 agonist, caused referred hyperalgesia in the lower abdomen, an effect prevented by capsazepine, a TRPV1 blocker. Tacrolimus accelerated the intracolonic capsaicin-induced referred hyperalgesia. Similarly, intracolonic capsaicin caused spinal ERK phosphorylation, a marker for nociceptor excitation, an effect promoted by tacrolimus. Thus, tacrolimus may aggravate TRPV1-related colonic pain accompanying irritable bowel syndrome.
• HMGB1 and its membrane receptors as therapeutic targets in an intravesical substance P-induced bladder pain syndrome mouse model.

  Yuhei Irie; Maho Tsubota; Mariko Maeda; Shiori Hiramoto; Fumiko Sekiguchi; Hiroyasu Ishikura; Hidenori Wake; Masahiro Nishibori; Atsufumi Kawabata

  Journal of pharmacological sciences 143 (2) 112 - 116 2020/06 [Refereed]
   

  HMGB1, a nuclear protein, once released to the extracellular space, promotes somatic and visceral pain signals. We thus analyzed the role of HMGB1 in an intravesical substance P-induced bladder pain syndrome (BPS) mouse model. Intravesical administration of substance P caused referred hyperalgesia/allodynia in the lower abdomen and hindpaw without producing severe urothelial damage, which was prevented by an anti-HMGB1-neutralizing antibody, thrombomodulin α capable of inactivating HMGB1 and antagonists of RAGE or CXCR4. The HMGB1 inactivation or RAGE blockade also reversed the established bladder pain symptoms. HMGB1 and RAGE are thus considered to serve as therapeutic targets for BPS.
• Involvement of macrophage-derived HMGB1 in acute pancreatits-related pain: roles of RAGE and cnR4 as the target molecules

  Irie Yuhei; Tsubota Maho; Sekiguchi Fumiko; Ishikura Hiroyasu; Nishibori Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 130 (3) S81  1347-8613 2016/03 [Refereed]
  
• Zinc deficiency-induced hyperalgesia in mice: involvement of Ca(v)3.2 and high mobility group box 1

  Tomita Shiori; Shikimi Shiyu; Sekiguchi Fumiko; Tsubota Maho; Shirai Akihiro; Nishibori Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 130 (3) S82  1347-8613 2016/03 [Refereed]
  
• Preventive and therapeutic effects of polaprezinc, a zinc-containing drug, on cyclophosphamide-induced cystitis and/or bladder pain

  Hiruma Saki; Murakami; Nakayama) Masahiro; Tsubota Maho; Sekiguchi Fumiko; Matsuyama Kenji; Kimura Takeshi; Moriyama Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 128 (3) S110  1347-8613 2015/07 [Refereed]
  
• Roles of macrophage-derived HMGB1 in a substance P-induced interstitial cystitis/bladder pain syndrome mouse model

  Maeda Mariko; Irie Yuhei; Tsubota Maho; Kubo Lisa; Sekiguchi Fumiko; Ishikura Hiroyasu; Nishibori Masahiro; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 130 (3) S144  1347-8613 2016/03 [Refereed]
  
• Effects of hydrogen sulfide on platelet aggregation and calcium mobilization in rabbits

  Hayashi Hitomi; Kubo Satoko; Nishikawa Hiroyuki; Sekiguchi Fumiko; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 106 95P  1347-8613 2008 [Refereed]
  
• Cell signaling for interleukin-8 release caused by PAR2 stimulation in human colorectal cancer and human gastric adenocarcinoma cells

  Tanaka Yusuke; Hong Hao; Sekiguchi Fumiko; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 106 101P  1347-8613 2008 [Refereed]
  
• Thiazolidinediones modulate PAR1-triggered prostaglandin E-2 production via PPAR gamma-independent mechanisms in rat normal gastric mucosal epithelial cells

  Takaoka Kaori; Shigi Hidenori; Sekiguchi Fumiko; Kawabata Atsufumi

  JOURNAL OF PHARMACOLOGICAL SCIENCES 106 211P  1347-8613 2008 [Refereed]
  

Books etc

• Inhibitory role of nitric oxide in the contraction of circular muscle of rat portal vein(共著)

  The Bioloby of Nitric Oxide Part 6 Portland Press Ltd, London 1998

Conference Activities & Talks

• Thrombomodulin/thrombin系で産生されるTAFIa/carboxypeptidase Bは補体成分C5aを不活性化することでoxaliplatin誘発性末梢神経障害を抑制する  [Not invited]

  圓尾賢悟; 坪田真帆; 田島和樹; 関口富美子; 西堀正洋; 南 達郎; 伊藤彰敏; 川畑篤史

  第95回日本薬理学会年会． 福岡
• RAGE拮抗薬azeliragonはヒト前立腺がん由来LNCaP細胞の生存・増殖を抑制する：影響をうける細胞シグナルの解析  [Not invited]

  芝野奈帆; 安達義史; 脇谷航平; 浅野絵莉茄; 関口富美子; 岡田卓哉; 西川裕之; 豊岡尚樹; 川畑篤史

  第95回日本薬理学会年会． 福岡
• 内因性H2S産生阻害による多発性骨髄腫細胞の生存抑制: カルビドパとベンセラジドのcystathionine-β-synthase阻害活性とボルテゾミブ耐性多発性骨髄腫治療への応用について  [Not invited]

  関口富美子; 森口晴香; 福島志歩; 井場祐里子; 坪田真帆; 平本志於里; 岡田卓哉; 豊岡尚樹; 田中宏和; 芦田隆司; 松村到; 川畑篤史

  第95回日本薬理学会年会．福岡
• Schwann cells from neonatal;rat;sciatic nerves;secrete high mobility group box 1 (HMGB); a pro-inflammatory and pro-nociceptive mediator;in response to paclitaxel  [Not invited]

  Sekiguchi, F; Yamashita, R; Yasui, H; Kawabata, A

  12th FENS Forum of Neuroscience; Glasgow; UK.  2020/07
• Middle molecular weight heparinylphenylalanine selectively blocks RAGE and reduces HMGB1-dependent neuropathic and visceral pain in mice.  [Not invited]

  Kawabata, A; Nishikawa; H. Higashimoto, K; Uenoyama, K; Sekiguchi, F; Tsubota1, M; Okada, T; Toyooka, N

  12th FENS Forum of Neuroscience, Glasgow, UK  2020/07
• Role of T-type calcium channels in methamphetamine-induced hyperlocomotion and neuronal excitation in mice.  [Not invited]

  Koike, N; Yasui, H; Sekiguchi, F; Tanabe, G; Kawabata, A

  AsCNP2019, Fukuoka, Japan  2019/10
• Paclitaxel, an anti-cancer drug, causes extracellular release of HMGB1, a pro-inflammatory and pro-nociceptive mediator, in Schwann cells derived from neonatal rat sciatic nerves.  [Not invited]

  Sekiguchi, F; Yamashita, R; Yasui, H; Kawabata, A

  AsCNP2019, Fukuoka, Japan  2019/10
• Crosstalk between the HMGB1/RAGE and CSE/H2S/Cav3.2 pathways involved in cystitis-related bladder pain in mice.  [Not invited]

  Hiramoto, S; Tsubota, M; Yamguchi, K; Okazaki, K; Tanaka, J; Sekiguchi, F; Ishikura, H; Nishibori, M; Kawabata, A

  EFIC Congress 2019, Pain in Europhe XI, Valencia, Spain
• 6-Prenylnaringenin and its derivative, KTt45, are mixed T-type Ca2+ channel inhibitors/CB2 receptor agonists: antinociceptive activity in neuropathic and visceral pain models.  [Not invited]

  Sekiguchi, F; Kasanami, Y; Onishi, R; Tsubota, M; Miyazaki, T; Hiramoto, S; Osazaki, K; Nguyen , D.U; Toyooka, N; Yoshida, S; Ohkubo, T; Kawabata, A

  EFIC Congress 2019, Pain in Europhe XI, Valencia, Spain
• Hepatic injury aggravates oxaliplatin-induced peripheral neuropathy in mice: possible involvement of HMGB1.  [Not invited]

  Domoto, R; Fukuda, R; Sekiguchi, F; Tsubota, M; Nishibori, M; Kawabata, A

  EFIC Congress 2019, Pain in Europhe XI, Valencia, Spain
• Middle Molecular Weight Heparinylphenylalanine Prevents the Development of Chemotherapy-Induced Peripheral Neuropathy in Mice.  [Not invited]

  Kawabata, A; Nishikawa, H; Uenoyama, K; Sekiguchi, F; Tsubota, M; Okada, T; Toyooka, N

  17th World Congress on Pain. Boston, USA
• AKAP-dependent modulation of phosphorylation levels of Cav3.2 T-type calcium channels by protein kinase A and calcineurin: implications for mechanical pain sensitivity.  [Not invited]

  吉田 繁; 関口 富美子; 坪田 真帆; 川畑 篤史

  Neuroscience 2011  2011/11  Washington, D.C., U.S.A.  Neuroscience 2011
  
• Sensitization of T-type calcium channels by prostaglandin E2 via the EP4 receptor/cyclic AMP/protein kinase A pathway: a possible mechanism for mechanical hyperalgesia.  [Not invited]

  吉田 繁; 関口 富美子; 坪田 真帆; 川畑 篤史

  Neuroscience 2011  2011/11  Washington, D.C., U.S.A.  Neuroscience 2011
  
• 脊髄後根神経節由来ND7/23細胞におけるcyclic AMP誘発神経突起伸長および電位依存性カルシウムチャネルの機能的増強．  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子

  第116回日本薬理学会近畿部会  2010/12  滋賀、大津  第116回日本薬理学会近畿部会
  
• マウス骨芽細胞前駆細胞におけるトロンビン受容体PAR1活性化によるプロスタグランジンE2産生に関与する細胞内シグナル．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第118回日本薬理学会近畿部会  2010/11  大阪  第118回日本薬理学会近畿部会
  
• Prostaglandin E2/cyclic AMP/protein kinase A系を介したT型カルシウムチャネルの機能増強－電気生理学的および行動薬理学的手法を用いた検討．  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁; 松波 真帆

  生体機能と創薬シンポジウム2010京都  2010/09  京都  生体機能と創薬シンポジウム2010京都
  
• マウス脊髄後根神経節培養細胞におけるprostaglandin E2誘発神経突起伸長メカニズムの解析．  [Not invited]

  川畑 篤史; 関口 富美子

  生体機能と創薬シンポジウム2010京都  2010/09  京都  生体機能と創薬シンポジウム2010京都
  
• アンドロゲン感受性前立腺癌細胞の神経内分泌様細胞への分化に伴う硫化水素産生酵素およびT型カルシウムチャネルの発現誘導：分泌機能調節における役割．  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子

  生体機能と創薬シンポジウム2010京都  2010/09  京都  生体機能と創薬シンポジウム2010京都
  
• 調剤薬局における薬剤師需要の動向予測に関する研究  [Not invited]

  長井 紀章; 川瀬 篤史; 木下 充弘; 関口 富美子; 桑島 博; 鈴木 茂生; 西田 升三; 松尾 圭造; 掛樋 一晃

  医療薬学フォーラム2010 第18回クリニカルファーマシーシンポジウム  2010/07  広島  医療薬学フォーラム2010 第18回クリニカルファーマシーシンポジウム
  
• Analysis of various biological responses induced by Helicobacter pylori extract: independent of proteinase-activated receptors?  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之; 松波 真帆

  6th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)  2010/07  デンマーク、コペンハーゲン  6th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)
  
• Prostaglandin E2により誘起される機械的痛覚過敏へのT型Ca2+チャネルの関与  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁; 松波 真帆

  第117回日本薬理学会近畿部会  2010/07  徳島  第117回日本薬理学会近畿部会
  
• Hydrogen sulfide promotes function of T-type calcium channels and secretion of prostatic acid phosphatase in neuroendocrine-like prostate cancer cells from the androgen-sensitive LNCaP cell line  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子

  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)  2010/07  デンマーク、コペンハーゲン  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)
  
• Analysis of cellular signaling for epidermal growth factor-mediated suppression of androgen-induced expression of prostate-specific antigen gene in human prostate cancer LNCaP cells  [Not invited]

  川畑 篤史; 関口 富美子

  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)  2010/07  デンマーク、コペンハーゲン  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)
   

  Maeda, Y., Yamanaka, R., Sekiguchi, F., Kawabata, A. , 2010, 7, 17-23, Copenhagen, Denmark.
• Peripheral hyperalgesia via the cyclic AMP/protein kinase A pathway involves activation of T-type calcium channels in rats.  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁

  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)  2010/07  デンマーク、コペンハーゲン  16th World Congress on Basic and Clinical Pharmacology (WorldPharma2010)
  
• 膵臓痛発現におけるプロテアーゼ、PAR2およびTRPV1の役割．  [Not invited]

  西村 幸容; 川畑 篤史; 関口 富美子; 松波 真帆

  第83回日本薬理学会年会  2010/03  大阪  第83回日本薬理学会年会
   

  19. 西村幸容、石倉宏恭、松波真帆、篠崎 結、関口富美子、成瀬光栄、喜多村泰輔、明石隆吉、松村謙二、川畑篤史. 第83回 日本薬理学会年会、2010, 3, 16-18, ．
• サイクリックAMPにより誘起される痛覚過敏へのT型カルシウムチャネルの関与.  [Not invited]

  川畑 篤史; 関口 富美子

  第83回日本薬理学会年会  2010/03  大阪  第83回日本薬理学会年会
  
• ラット後根神経節由来ND7/23細胞においてcyclic AMPにより誘発される神経突起伸長およびイオンチャネル機能増強の特徴.  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁

  第83回 日本薬理学会年会  2010/03  大阪  第83回 日本薬理学会年会
  
• 膵炎関連痛モデルにおけるメシル酸カモスタットの抗侵害受容的作用．  [Not invited]

  西村 幸容; 川畑 篤史; 関口 富美子; 辻内 俊文; 松波 真帆

  第79回日本薬理学会年会  2010  横浜  第79回日本薬理学会年会
  
• Helicobacter pylori抽出液により誘起される種々の細胞反応：Proteinase-activated receptor関与の有無について．  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之; 松波 真帆

  第116回日本薬理学会近畿部会  2009/11  滋賀、大津  第116回日本薬理学会近畿部会
   

  1. 関口富美子, 前田優磨, 松本裕喜, 松波真帆, 西川裕之, 川畑篤史. 、2009, 11, 13, 大津．
• Involvement of downstream Src activation of Cav3.2 T-type calcium channels in hydrogen sulfide-induced neuronal differentiation in NG108-15 cells.  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁

  13th Congress of the European Federation of Neurological Societies (EFNS 2009)  2009/09  イタリア、フィレンツェ  13th Congress of the European Federation of Neurological Societies (EFNS 2009)
  
• Neurite outgrowth and functional up-regulation of voltage-dependent calcium channels caused by cyclic AMP in sensory neuron-like cells.  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁

  13th Congress of the European Federation of Neurological Societies (EFNS 2009)  2009/09  イタリア、フィレンツェ  13th Congress of the European Federation of Neurological Societies (EFNS 2009)
  
• Effect of Helicobacter pylori extracts on prostaglandin E2 production in human lung alveolar epithelial A549 cells.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  XXXVI International Congress of Physiological Sciences  2009/08  日本、京都  XXXVI International Congress of Physiological Sciences
  
• The time lag of PGE2 release and COX-2 up-regulation triggered by PAR1 is due to deficiency of arachidonic acid in gastric epithelial cells.  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之

  XXXVI International Congress of Physiological Sciences  2009/08  日本、京都  XXXVI International Congress of Physiological Sciences
  
• げっ歯類の気道および消化管平滑筋の緊張性におよぼす硫化水素の影響．  [Not invited]

  関口 富美子; 川畑 篤史

  第51回日本平滑筋学会総会  2009/07  名古屋  第51回日本平滑筋学会総会
  
• The delayed release of PGE2 mediated by PAR1 involves slowly developing production of arachidonic acid in rat gastric mucosal epithelical cells.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  Experimental Biology 2009  2009/04  アメリカ合衆国、ニューオリンズ  Experimental Biology 2009
  
• Relationship between expression of PARs and infection with H. pylori in the stomach of gastric cancer patients.  [Not invited]

  川畑 篤史; 関口 富美子

  Experimental Biology 2009  2009/04  アメリカ合衆国、ニューオリンズ  Experimental Biology 2009
  
• IL-8 release triggered by proteinase-activated receptor-2 stimulation involves both MEK/ERK and PI3 kinase/Akt pathways in gastrointestinal epithelial cells.  [Not invited]

  関口 富美子; 川畑 篤史

  Experimental Biology 2009  2009/04  アメリカ合衆国、ニューオリンズ  Experimental Biology 2009
  
• 硫化水素はCav3.2 T型カルシウムチャネルの活性化に続くSrc型チロシンキナーゼの活性化を介してNG108-15細胞の神経分化を誘導する．  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子

  第82回日本薬理学会年会  2009/03  横浜  第82回日本薬理学会年会
  
• 内因性硫化水素の標的分子Cav3.2 T型カルシウムチャネルは神経因性疼痛の保持において重要な役割を示す  [Not invited]

  川畑 篤史; 関口 富美子; 竹村 元秀

  第82回日本薬理学会年会  2009/03  横浜  第82回日本薬理学会年会
  
• 硫化水素により誘起される大脳皮質神経細胞死のメカニズムの解析：特にMEK/ERK系の関与について．  [Not invited]

  川畑 篤史; 関口 富美子; 福嶋 伸之; 赤池昭紀; 久米

  第82回日本薬理学会年会  2009/03  横浜  第82回日本薬理学会年会
  
• 胃癌患者より摘出した胃組織のヘリコバクター・ピロリ由来ウレアーゼ蛋白量とPAR1あるいはPAR2発現量の相関性について．  [Not invited]

  関口 富美子; 川畑 篤史

  第82回日本薬理学会年会  2009/03  横浜  第82回日本薬理学会年会
  
• 硫化水素によるNG108-15細胞の神経分化はT型カルシウムチャネル活性化に続くSrc型チロシンキナーゼ活性化に依存する．  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子

  第114回日本薬理学会近畿部会  2008/11  神戸  第114回日本薬理学会近畿部会
  
• マウス胎児大脳皮質神経細胞における内因性ガスメッセンジャー硫化水素の神経細胞毒性はMEK-ERK系の活性化に依存する．  [Not invited]

  川畑 篤史; 福嶋 伸之; 関口 富美子; 赤池昭紀; 久米

  第114回日本薬理学会近畿部会  2008/11  神戸  第114回日本薬理学会近畿部会
  
• Hydrogen sulfide induces neuronal differentiation via Cav3.2 T-type calcium channels and Src family tyrosine kinase in NG108-15 cells.  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子; 松波 真帆; 西川 裕之

  6th FENS Forum of European Neuroscience  2008/07  スイス、ジュネーブ  6th FENS Forum of European Neuroscience
  
• Involvement of endogenous hydrogen sulfide in acute pancreatitis-related pain.  [Not invited]

  西村 幸容; 川畑 篤史; 辻内 俊文; 関口 富美子; 松波 真帆

  6th FENS Forum of European Neuroscience  2008/07  スイス、ジュネーブ  6th FENS Forum of European Neuroscience
  
• Cell damage induced by hydrogen sulfide in cortical neurons from mouse embryos.  [Not invited]

  関口 富美子; 川畑 篤史; 吉田 繁; 赤池 昭紀; 久米

  6th FENS Forum of European Neuroscience  2008/07  スイス、ジュネーブ  6th FENS Forum of European Neuroscience
  
• Hydrogen sulfide is pro-nociceptive in the spinal cord as well as peripheral tissues.  [Not invited]

  川畑 篤史; 吉田 繁; 関口 富美子; 西川 裕之

  6th FENS Forum of European Neuroscience  2008/07  スイス、ジュネーブ  6th FENS Forum of European Neuroscience
  
• 近畿大学における薬学生と医学生の合同PBLの試み  [Not invited]

  木村 健; 関口 富美子; 大鳥 徹; 上硲 俊法; 木村 雅友; 吉田 浩二

  日本薬学会第128年会  2008/03  横浜  日本薬学会第128年会
   

  近畿大学薬学部・医学部合同学習会におけるPBL教育に関する報告。
• 脊髄内および末梢組織中の硫化水素による痛覚過敏発現におけるCav3.2 T型カルシウムチャネルとNMDA受容体の役割．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• ラット正常胃粘膜上皮細胞においてチアゾリジンディオン系薬物はPAR1活性化によるプロスタグランジンE2産生をPPARγ非依存性に修飾する．  [Not invited]

  川畑 篤史; 関口 富美子

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• ヒト肺胞上皮細胞においてPAR2活性化により誘起されるプロスタグランジンE2産生に対するクルクミンの効果．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• ラット胃粘膜上皮細胞RGM1においてproteinase-activated receptor-1を介したprostaglandin E2産生亢進の遅延はアラキドン酸供給不足に起因する．  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之

  第26回Cytoprotection研究会  2008/03  京都  第26回Cytoprotection研究会
  
• ラット胃粘膜上皮細胞におけるproteinase-activated receptor-1刺激誘起遅発性プロスタグランジンE2産生亢進に関わる細胞内情報伝達系の検討．  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• ヒト結腸癌および胃腺癌由来細胞においてPAR2刺激により誘起されるインターロイキン-8遊離に関与する細胞シグナル．  [Not invited]

  川畑 篤史; 関口 富美子

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• ウサギ血小板の凝集およびカルシウム動員におよぼす硫化水素の影響．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第81回日本薬理学会年会  2008/03  横浜  第81回日本薬理学会年会
  
• Hydrogen sulfide as a nociceptive messenger in rat and mouse pancreata.  [Not invited]

  川畑 篤史; 関口 富美子; 松波 真帆; 辻内 俊文; 西村 幸容

  Neuroscience 2007  2007/11  アメリカ合衆国、サンディエゴ  Neuroscience 2007
   

  4. Kawabata, A., Nishimura, S. 西村幸容, Fukushima, O., Ishikura, H., Takahashi, T., Matsunami, M., Tsujiuchi, T., Sekiguchi, F., Naruse, M., Kamanaka, Y. , 2007, 11, 3-7, Dan Diego, USA.
• ヒト肺胞由来上皮細胞におけるPAR2誘起プロスタグランジンE2産生亢進に対するクルクミンの抑制効果．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之; 守行 和美; 松原 かおり

  第112回日本薬理学会近畿部会  2007/11  大阪  第112回日本薬理学会近畿部会
   

  3. 守行和美、松原かおり、関口富美子、西川裕之、川畑篤史．、2007, 11, 16, 豊中．
• ラット正常胃粘膜上皮RGM1細胞におけるPAR1活性化誘起プロスタグランジンE2産生に対するチアゾリジンディオン系薬物の影響．  [Not invited]

  川畑 篤史; 関口 富美子; 高岡 香保理; 信貴 秀矩

  第112回日本薬理学会近畿部会  2007/11  大阪  第112回日本薬理学会近畿部会
  
• 脊髄内および末梢組織内の硫化水素による痛覚過敏：CaV3.2 T型カルシウムチャネルの関与について．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第112回日本薬理学会近畿部会  2007/11  大阪  第112回日本薬理学会近畿部会
  
• H2Sと平滑筋運動．シンポジウム「気体メディエーターと創薬」  [Not invited]

  関口 富美子; 川畑 篤史; 西川 裕之

  生体機能と創薬シンポジウム2007金沢  2007/09  石川  生体機能と創薬シンポジウム2007金沢
  
• A pro-nociceptive role for hydrogen sulfide in the pancreas.  [Not invited]

  川畑 篤史; 関口 富美子; 松波 真帆; 西村 幸容

  The 4th Science and Research Symposium:  2007/08  名古屋  The 4th Science and Research Symposium:
   

  9. Kawabata, A., Nishimura, S., Fukushima, O., Ishikura, H., Takahashi, T., Matsunami, M., Sekiguchi, F., Naruse, M. 2007, 8, 28, Nagoya.
• Inhibition of the activity of three recombinant nitric oxide synthase isoforms by hydrogen sulfide.  [Not invited]

  川畑 篤史; 関口 富美子

  Young Life Scientists’ Symposium 2007  2007/07  イギリス、グラスゴー  Young Life Scientists’ Symposium 2007
  
• Hydrogen sulfide (H2S) as a hypothetical pro-inflammatory signaling molecule in ulcerative colitis (UC): impaired detoxification but not generation of H2S in a mouse UC model.  [Not invited]

  川畑 篤史; 関口 富美子; 松波 真帆; 西川 裕之

  Young Life Scientists’ Symposium 2007  2007/07  イギリス、グラスゴー  Young Life Scientists’ Symposium 2007
  
• Modulation of PAR1-triggered prostaglandin E2 production by thiazolidinediones through peroxisome proliferator-activated receptor-γ-independent pathways in rat gastric mucosal epithelial cells.  [Not invited]

  川畑 篤史; 関口 富美子

  Young Life Scientists’ Symposium 2007  2007/07  イギリス、グラスゴー  Young Life Scientists’ Symposium 2007
  
• Curcumin intervention of PAR2-triggered prostaglandin E2 (PGE2) release in human lung epithelial cells: what are the target molecules downstream of PAR2?  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  Young Life Scientists’ Symposium 2007  2007/07  イギリス、グラスゴー  Young Life Scientists’ Symposium 2007
  
• Effects of hydrogen sulfide on the tone of gastrointestinal and airway smooth muscle preparations from rodents.  [Not invited]

  関口 富美子; 川畑 篤史

  Life Sciences 2007  2007/07  イギリス、グラスゴー  Life Sciences 2007
  
• ．硫化水素はNG108-15細胞においてT型カルシウムチャネルのレドックス制御を介して神経分化を誘起する．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之; 吉田 繁; 市田 成志

  第80回日本薬理学会年会  2007/03  名古屋  第80回日本薬理学会年会
  
• ガスメッセンジャー硫化水素は膵臓の痛みに関与する．  [Not invited]

  川畑 篤史; 関口 富美子; 松波 真帆; 西村 幸容

  第80回日本薬理学会年会  2007/03  名古屋  第80回日本薬理学会年会
  
• 炎症性腸疾患(IBD)モデルにおける硫化水素産生・解毒に関与する酵素の挙動  [Not invited]

  川畑 篤史; 関口 富美子; 松波 真帆

  第80回日本薬理学会年会  2007/03  名古屋  第80回日本薬理学会年会
  
• ガスメッセンジャーH2Sの膵炎関連痛への関与  [Not invited]

  西村 幸容; 川畑 篤史; 関口 富美子; 松波 真帆

  第110回 日本薬理学会近畿部会  2006/11  京都  第110回 日本薬理学会近畿部会
  
• Hydrogen sulfide sensitizes T-type calcium channels via redox modulation.  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁; 市田 成志; 和田 哲幸; 西川 裕之

  Neuroscience 2006  2006/10  アメリカ合衆国、アトランタ  Neuroscience 2006
  
• トロンビン受容体PAR1活性化を介したラット胃粘膜上皮細胞からの遅延性プロスタグランジンE2産生亢進に関与する細胞内情報伝達系の検討．  [Not invited]

  関口 富美子; 川畑 篤史; 河尾 直之

  第56回日本薬学会近畿支部総会・大会  2006/10  京都  第56回日本薬学会近畿支部総会・大会
  
• Prostaglandin E2 production triggered by proteinase-activated receptor-1 in rat gastric mucosal epithelial cells: Cell signaling and modulation by peroxisome proliferator-activated receptor-γ ligands.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  Half-day Symposium on G Protein-Coupled Receptors (GPCRs)  2006/09  箱根  Half-day Symposium on G Protein-Coupled Receptors (GPCRs)
  
• Proteinase-activated receptor活性化によるプロスタノイド産生シグナルと病態．  [Not invited]

  関口 富美子; 川畑 篤史

  第34回 薬物活性シンポジウム  2006/09  群馬  第34回 薬物活性シンポジウム
  
• Evidence that hydrogen sulfide plays a pro-nociceptive role.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之; 吉田 繁

  The 18th Japan-Korea Joint Seminar of Pharmacology, 2006, 9, 23-24, Fukui.  2006/09  福井  The 18th Japan-Korea Joint Seminar of Pharmacology, 2006, 9, 23-24, Fukui.
  
• COX-2 up-regulation and prostaglandin E2 production triggered by proteinase-activated receptor-1 (PAR1) and their facilitation by peroxisome proliferator-activated receptor-γ ligands in rat gastric mucosal epithelial cells.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  The Inernational Mini-Symposium on Gastrointestinal Pharmacology  2006/07  京都  The Inernational Mini-Symposium on Gastrointestinal Pharmacology
  
• 内因性ガス状情報伝達物質H2SによるＴ型カルシウムチャネルの感受性増大と痛覚過敏の発現．  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁

  第28回日本疼痛学会  2006/07  神戸  第28回日本疼痛学会
  
• 内因性ガス状情報伝達物質H2Sは未分化NG108-15細胞においてＴ型カルシウムチャネルの感受性を増大させる．  [Not invited]

  川畑 篤史; 関口 富美子; 吉田 繁; 市田 成志; 和田 哲幸; 西川 裕之

  第109回日本薬理学会近畿部会  2006/06  岡山  第109回日本薬理学会近畿部会
  
• 新規内因性ガスメッセンジャー硫化水素によるマウス気管支平滑筋の弛緩．  [Not invited]

  川畑 篤史; 関口 富美子

  第79回日本薬理学会年会  2006/03  横浜  第79回日本薬理学会年会
  
• ラット胃血管緊張性および粘膜循環動態におよぼすガスメッセンジャー硫化水素の効果．  [Not invited]

  川畑 篤史; 関口 富美子

  第79回日本薬理学会年会  2006/03  横浜  第79回日本薬理学会年会
  
• 内因性ガスメッセンジャー硫化水素のラット胃粘膜における保護的役割．  [Not invited]

  川畑 篤史; 関口 富美子

  第79回日本薬理学会年会  2006/03  横浜  第79回日本薬理学会年会
  
• 新しい内因性疼痛情報伝達物質としての硫化水素の役割．  [Not invited]

  川畑 篤史; 関口 富美子

  第79回日本薬理学会年会  2006/03  横浜  第79回日本薬理学会年会
  
• ヒト肺胞上皮細胞においてPAR2活性化により誘起されるIL-8およびprostaglandin E2産生亢進に関与する細胞内シグナルについて．  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  第79回日本薬理学会年会  2006/03  横浜  第79回日本薬理学会年会
  
• Distinct signaling and actions caused by intracellular ligands (pepducins) for proteinase-activated receptor-1 in multiple cells/tissues.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  Cell Signaling World 2006  2006/01  ルクセンベルグ  Cell Signaling World 2006
  
• Cell signaling by proteinase-activated receptor-2 for interleukin-8 formation in human lung epithelial cells.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之

  Cell Signaling World  2006/01  ルクセンブルク  Cell Signaling World
   

  33. Kawabata, A., Nagataki, M., Moriyuki, K., Sekiguchi, F., Nishikawa, H. 2006, 1, 25-28, Luxembourg. (Oral presentation)
• ヒト肺胞上皮細胞におけるPAR-2活性化によるCOX-2の誘導とそれに関与するシグナルの解析  [Not invited]

  川畑 篤史; 河尾 直之; 和田 哲幸; 関口 富美子; 市田 成志; Wallace K. MacNaughton; Morley D. Hollenberg

  第106回日本薬理学会近畿部会  2004/11  京都  第106回日本薬理学会近畿部会
  
• 細胞内PAR-1アゴニストペプチドおよびアンタゴニストペプチド(pepducins)の各種細胞・組織における作用の解析  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之; 田

  第106回日本薬理学会近畿部会  2004/11  京都  第106回日本薬理学会近畿部会
  
• 化器疾患治療における新しい創薬標的分子としてのprotease-activated receptors (PARs)  [Not invited]

  川畑 篤史; 関口 富美子

  第32回薬物活性シンポジウム  2004/11  大阪  第32回薬物活性シンポジウム
  
• トロンビン受容体PAR-1活性化を介したラット胃粘膜上皮細胞からの遅延性プロスタグランジンE2産生亢進に関与する細胞内情報伝達系の検討  [Not invited]

  関口 富美子; 河尾 直之; 川畑 篤史; 西川 裕之; 荒木

  第５４回日本薬学会近畿支部大会  2004/10  神戸  第５４回日本薬学会近畿支部大会
  
• Luminal trypsin causes delayed facilitation of capsaicin-evoked visceral nociception by activating protease-activated receptor-2.  [Not invited]

  川畑 篤史; 河尾 直之; 関口 富美子; 松波 真帆; 黒田 良太郎; 菅家 徹

  Neuroscience 2004  2004/10  San Diego, USA  Neuroscience 2004
  
• Protease-activated receptors (PARs) and respiratory functions: cellular signaling and enhancement of prostanoid formation in the epithelium.  [Not invited]

  川畑 篤史; 河尾 直之; 関口 富美子; Morely D. Hollenberg; Wallace K. MacNaughton; 西川 裕之

  The 17th Korea-Japan Joint Seminar on Pharmacology  2004/09  Jeonju, Korea  The 17th Korea-Japan Joint Seminar on Pharmacology
  
• Inhibitory and excitatory modulations of mouse gastrointestinal motility by activation of proteinase-activated receptor (PAR)-1 and PAR-2.  [Not invited]

  関口 富美子; 川畑 篤史; 菅家 徹

  The 17th Korea-Japan Joint Seminar on Pharmacology  2004/09  Jeonju, Korea  The 17th Korea-Japan Joint Seminar on Pharmacology
  
• The intracellular agonist and antagonist (pepducins) for proteinase-activated receptor-1: distinct activity in multiple cells/tissues.  [Not invited]

  川畑 篤史; 関口 富美子; 西川 裕之; 田

  The 17th Korea-Japan Joint Seminar on Pharmacology  2004/09  Jeonju, Korea  The 17th Korea-Japan Joint Seminar on Pharmacology
  
• Protease-activated receptor-2の新規高活性アゴニスト2-furoyl-LIGRL-NH2: in vitroおよびin vivoにおける活性評価  [Not invited]

  川畑 篤史; 関口 富美子; 岩城 正宏; 菅家 徹

  第9回病態と治療におけるプロテアーゼとインヒビター研究会  2004/07  名古屋  第9回病態と治療におけるプロテアーゼとインヒビター研究会
  
• Protease-activated receptor-1活性化による胃粘膜上皮細胞からのprostaglandin E2産生亢進に関与する細胞内メカニズムの検討  [Not invited]

  関口 富美子; 河尾 直之; 川畑 篤史; 西川 裕之; 荒木

  第9回病態と治療におけるプロテアーゼとインヒビター研究会  2004/07  名古屋  第9回病態と治療におけるプロテアーゼとインヒビター研究会
  
• Protease-activated receptor-2 activation induces delayed facilitation of capsaicin-evoked visceral pain in mice: involvement of endogenous bradykinin.  [Not invited]

  川畑 篤史; 河尾 直之; 関口 富美子; 黒田 良太郎; 菅家 徹

  11th International Pain Clinic World Society of Pain Clinicians  2004/07  東京  11th International Pain Clinic World Society of Pain Clinicians
  
• ラット胃粘膜上皮細胞RGM1におけるPAR-1活性化を介したPGE2産生亢進と関連する細胞内シグナル  [Not invited]

  関口 富美子; 河尾 直之; 川畑 篤史; 西川 裕之; 荒木

  第105回日本薬理学会近畿部会  2004/06  徳島  第105回日本薬理学会近畿部会
  
• カラゲニン誘発熱痛覚過敏に対する誘導型NO合成酵素（iNOS）阻害薬ONO-1714の鎮痛効果  [Not invited]

  関口 富美子; 河尾 直之; 川畑 篤史

  日本薬学会第124年会  2004/03  大阪  日本薬学会第124年会
  
• 内臓痛発現におけるPAR-2とプロテアーゼの役割：PAR-2ノックアウトマウスおよびメシル酸ナファモスタットを用いた検討  [Not invited]

  河尾 直之; 川畑 篤史; 関口 富美子; 黒田 良太郎; 菅家 徹

  日本薬学会第124年会  2004/03  大阪  日本薬学会第124年会
  
• Signal transduction mechanisms for prostanoid formation caused by protease-activated receptor-2 activation in human lung epithelial cells.  [Not invited]

  川畑 篤史; 河尾 直之; 和田 哲幸; 市田 成志; 関口 富美子; Morley D. Hollenberg

  XVIIth International Congress on Fibrinolysis and Proteolysis  2004/03  Melbourne, Australia  XVIIth International Congress on Fibrinolysis and Proteolysis
  
• Roles of protease-activated receptor-1 and -2 in modulation of mouse gastrointestinal motility.  [Not invited]

  関口 富美子; 川畑 篤史

  XVIIth International Congress on Fibrinolysis and Proteolysis  2004/03  Melbourne, Australia  XVIIth International Congress on Fibrinolysis and Proteolysis
  
• Mechanisms underlying contraction/relaxation caused by activation of protease-activated receptors 1 and 2 in rat superior mesenteric artery.  [Not invited]

  川畑 篤史; 黒田 良太郎; 関口 富美子; 西 川 裕 之

  XVIIth International Congress on Fibrinolysis and Proteolysis  2004/03  Melbourne, Australia  XVIIth International Congress on Fibrinolysis and Proteolysis
  
• PAR-1およびPAR-2活性化によるマウス消化管運動調節機構  [Not invited]

  関口 富美子; 川畑 篤史

  第77回日本薬理学会年会  2004/03  大阪  第77回日本薬理学会年会
  
• ビスホスホネート系薬剤エチドロネートはATP感受性カリウムチャネルを介してアジュバント関節炎ラットにおけるアロディニアを抑制する  [Not invited]

  河尾 直之; 川畑 篤史; 関口 富美子

  第77回日本薬理学会年会  2004/03  大阪  第77回日本薬理学会年会
  
• PAR-2およびPAR-1活性化によるマウス気道平滑筋弛緩反応メカニズムの解析  [Not invited]

  川畑 篤史; 河尾 直之; 関口 富美子; Morley D. Hollenberg

  第77回日本薬理学会年会  2004/03  大阪  第77回日本薬理学会年会
  
• Pulmonary arterial pressure of WKY and SHRSP  [Not invited]

  山本 和夫; 島村 佳一; 松田 恭子; 関口 富美子; 砂野 哲

  第３６回高血圧自然発症ラット(SHR)学会総会  2000/07  京都  第３６回高血圧自然発症ラット(SHR)学会総会
   

  WKY、SHRSPとも肺動脈圧は、大腿動脈圧に比べ著しい低値を示した。摘出肺動脈の、内皮依存性弛緩には、間に差はなく、低度の肺動脈圧上昇は、内皮依存性の弛緩には依存しないためと考えられた。

MISC

• アンギオテンシン変換酵素阻害薬とアンギオテンシンII受容体拮抗薬は糖尿病性末梢神経障害の発症を抑制する:臨床・基礎融合研究によるエビデンス

  冨田詩織; 冨田詩織; 宮本朋佳; 宮本朋佳; 田中雅幸; 打谷和記; 小泉祐一; 村中達也; 根本亙; 丹野孝一; 坪田真帆; 関口富美子; 川畑篤史  生体機能と創薬シンポジウム要旨集  2022-  2022
• Thrombomodulin alfaのoxaliplatin誘発性末梢神経障害抑制作用発現におけるHMGB1不活性化とprotein C及びTAFI活性化の相対的重要性と下流シグナル分子の解析

  圓尾賢悟; 坪田真帆; 田島和樹; 関口富美子; 西堀正洋; 南達郎; 伊藤彰敏; 川畑篤史  日本薬理学雑誌  157-  (Supplement)  2022
• 抗リウマチ薬sulfasalazineはマクロファージからのHMGB1遊離を抑制することでlipopolysaccharide誘起アロディニアを抑制する

  堂本莉紗; 田村ひなの; 関口富美子; 坪田真帆; 西堀正洋; 川畑篤史  日本薬理学雑誌  157-  (Supplement)  2022
• Oxaliplatin誘起末梢神経障害には血小板由来HMGB1が関与する

  岸本彩野; 堂本莉紗; 松永浩明; 松本亜紗菜; 坪田真帆; 関口富美子; 王登莉; 西堀正洋; 川畑篤史  日本薬理学雑誌  157-  (Supplement)  2022
• Sulfide-induced facilitation of Cav3.2 activity and pain sensitivity, and its inhibition by repagermanium capable of trapping sulfide

  関口富美子; 増田寛志; 笠波嘉人; 小池寧々; 南郷優希; 島田康弘; 杉本果歩; 佐藤克行; 中村宜司; 山口浩明; 田邉元三; 丸本真輔; 坪田真帆; 川畑篤史  Pain Research  37-  (4)  2022
• Anti-platelet agents prevent oxaliplation-induced peripheral neuropathy (OIPN): involvement of platelet-derived HMGB1 in OIPN

  川畑篤史; 岸本彩野; 堂本莉紗; 松永浩明; 松本亜紗菜; 坪田真帆; 関口富美子; WANG Dengli; 西堀正洋  Pain Research  37-  (4)  2022
• Distinct mechanisms for release of HMGB1 from macrophages involved in the peripheral neuropathy induced by chemotherapeutic agents, bortezomib and vincristine

  青木葉優衣; 谷津健太; 池田裕哉; 関口富美子; 坪田真帆; WANG Dengli; 西堀正洋; 川畑篤史  日本薬学会年会要旨集(Web)  142nd-  2022
• 中分子ヘパリニルフェニルアラニンはRAGEが関与する痛みを抑制する

  東本紅瑠美; 上野山桐子; 西川裕之; 西川裕之; 関口富美子; 坪田真帆; 岡田卓哉; 豊岡尚樹; 川畑篤史  日本薬理学雑誌  156-  (Supplement)  2021
• 有機ゲルマニウム化合物repagermaniumのH₂S/Ca_v3.2を介した体性痛および内臓痛に対する抑制効果

  関口富美子; 小池寧々; 島田康弘; 杉本果歩; 増田寛志; 佐藤克行; 中村宜司; 山口浩明; 田邉元三; 丸本真輔; 笠波嘉人; 坪田真帆; 川畑篤史  日本薬理学雑誌  156-  (Supplement)  2021
• 新規Ca_V3.2阻害剤NCP-1117の薬理プロファイル

  田中博人; 田中博人; 小川亨; 中村英生; 坪田真帆; 小松隆男; 今井利安; 山川富雄; 関口富美子; 川畑篤史  日本薬理学雑誌  156-  (Supplement)  2021
• H₂S供与体Na₂Sのマウス頬皮内投与により誘起されるCa_v3.2依存性掻痒および疼痛に対する定型抗精神病薬pimozideとD₂受容体遮断活性を減弱させた新規pimozide誘導体KTtp-5の作用

  倉橋翔太郎; 西山伊代; 南野莉那; 木野貴博; 高島康宏; 笠波嘉人; 木野志織; 西川裕之; 西川裕之; 石川千浩; 岡田卓哉; 岡田卓哉; 関口富美子; 坪田真帆; 豊岡尚樹; 豊岡尚樹; 川畑篤史  日本薬理学雑誌  156-  (Supplement)  2021
• マウスにおけるbortezomib誘発性末梢神経障害の発症および維持におけるHMGB1の役割とその起源

  池田裕哉; 宮崎貴也; 坪田真帆; 冨田詩織; 関口富美子; 西堀正洋; 川畑篤史  日本薬理学雑誌  154-  (Supplement)  2019
• Roles of HMGB1 and its target molecules in the oxaliplatin-induced neuropathic pain: independence of macrophages

  Maho Tsubota; Ryotaro Fukuda; Fumiko Sekiguchi; Takaya Miyazaki; Risa Domoto; Hiroki Yasui; Takeshi Nishida; Hiroyasu Ishikura; Masahiro Nishibori; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  133-  (3)  S97  -S97  2017/03
• P-15.げっ歯類の気道および消化管平滑筋の緊張性におよぼす硫化水素の影響(ポスター発表,一般演題,第51回日本平滑筋学会総会)

  関口 富美子; 久保 聡子; 黒河 祐子; 岡本 由佳梨; 土江位 知子; 川畑 篤史  日本平滑筋学会雑誌  13-  (1)  "J  -30"  2009/06
• 消化器疾患治療における新しい創薬標的分子としての protease-activated receptors (PARs)

  川畑 篤史; 関口 富美子  日本薬理学雑誌 : FOLIA PHARMACOLOGICA JAPONICA  124-  89P  -90P  2004/11
• Receptor-activating peptides for PAR-1 and PAR-2 relax rat gastric artery via multiple mechanisms

  A Kawabata; Y Nakaya; T Ishiki; S Kubo; R Kuroda; F Sekiguchi; N Kawao; H Nishikawa; K Kawai  LIFE SCIENCES  75-  (22)  2689  -2702  2004/10
• Proteinase-activated receptor-2-mediated relaxation in mouse tracheal and bronchial smooth muscle: Signal transduction mechanisms and distinct agonist sensitivity

  A Kawabata; S Kubo; T Ishiki; N Kawao; F Sekiguchi; R Kuroda; MD Hollenberg; T Kanke; N Saito  JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS  311-  (1)  402  -410  2004/10
• Activation of trigeminal nociceptive neurons by parotid PAR-2 activation in rats

  A Kawabata; H Itoh; N Kawao; R Kuroda; F Sekiguchi; T Masuko; K Iwata; A Ogawa  NEUROREPORT  15-  (10)  1617  -1621  2004/07
• The potent inducible nitric oxide synthase inhibitor ONO-1714 inhibits neuronal NOS and exerts antinociception in rats

  F Sekiguchi; Y Mita; Y Kamanaka; N Kawao; H Matsuya; C Taga; A Kawabata  NEUROSCIENCE LETTERS  365-  (2)  111  -115  2004/07
• Potent and metabolically stable agonists for protease-activated receptor-2: Evaluation of activity in multiple assay systems in vitro and in vivo

  A Kawabata; T Kanke; D Yonezawa; T Ishiki; M Saka; M Kabeya; F Sekiguchi; S Kubo; R Kuroda; M Iwaki; K Katsura; R Plevin  JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS  309-  (3)  1098  -1107  2004/06
• Superoxide dismutase reduces the impairment of endothelium-dependent relaxation in the spontaneously hypertensive rat aorta

  Fumiko Sekiguchi; Aiko Yanamoto; Satoru Sunano  Journal of Smooth Muscle Research  40-  (2)  65  -74  2004/04
• Distinct roles for protease-activated receptors 1 and 2 in vasomotor modulation in rat superior mesenteric artery

  A Kawabata; S Kubo; Y Nakaya; T Ishiki; R Kuroda; F Sekiguchi; N Kawao; H Nishikawa  CARDIOVASCULAR RESEARCH  61-  (4)  683  -692  2004/03
• Abnormal response to ryanodine in oesophageal striated muscle of spontaneously hypertensive rats

  F Sekiguchi; K Kawata; M Yamazoe; S Sunano  EUROPEAN JOURNAL OF PHARMACOLOGY  486-  (1)  91  -98  2004/02
• Protease-activated receptors (PARs) as therapeutic targets: development of agonists/antagonists and modulation of gastrointestinal functions.

  Drug Design Rev.  in press-  2004
• Modulation of capsaicin-evoked visceral pain and referred hyperalgesia by protease-activated receptors 1 and 2

  N Kawao; H Ikeda; T Kitano; R Kuroda; F Sekiguchi; K Kataoka; Y Kamanaka; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  94-  (3)  277  -285  2004/03
• A protective role of protease-activated receptor 1 in rat gastric mucosa

  A Kawabata; H Nishikawa; H Saitoh; Y Nakaya; K Hiramatsu; S Kubo; M Nishida; N Kawao; R Kuroda; F Sekiguchi; M Kinoshita; K Kakehi; N Arizono; H Yamagishi; K Kawai  GASTROENTEROLOGY  126-  (1)  208  -219  2004/01
• Effect of a potent iNOS inhibitor (ONO-1714) on acetaminophen-induced hepatotoxicity in the rat

  Y Kamanaka; A Kawabata; H Matsuya; C Taga; F Sekiguchi; N Kawao  LIFE SCIENCES  74-  (6)  793  -802  2003/12
• The PAR-1-activating peptide facilitates pepsinogen secretion in rats

  N Kawao; K Hiramatsu; N Inoi; R Kuroda; H Nishikawa; F Sekiguchi; A Kawabata  PEPTIDES  24-  (9)  1449  -1451  2003/09
• Contraction of arterial smooth muscle of normotensive and spontaneously hypertensive rats by manganese(III)tetrakis(1-methyl-4-pyridyl)porphyrin (MnTMPyP)

  F Sekiguchi; M Seo; S Sunano  JOURNAL OF PHARMACOLOGICAL SCIENCES  92-  (2)  163  -165  2003/06
• Contraction of arterial smooth muscle of normotensive and spontaneously hypertensive rats by manganese(III)tetrakis(1-methyl-4-pyridyl)porphyrin (MnTMPyP)

  F Sekiguchi; M Seo; S Sunano  JOURNAL OF PHARMACOLOGICAL SCIENCES  92-  (2)  163  -165  2003/06
• Caffeine-induced contracture in oesophageal striated muscle of normotensive and hypertensive rats

  F Sekiguchi; K Kawata; M Komori; S Sunano  EUROPEAN JOURNAL OF PHARMACOLOGY  465-  (1-2)  153  -161  2003/03
• Caffeine-induced contracture in oesophageal striated muscle of normotensive and hypertensive rats

  F Sekiguchi; K Kawata; M Komori; S Sunano  EUROPEAN JOURNAL OF PHARMACOLOGY  465-  (1-2)  153  -161  2003/03
• Effects of L-arginine on spontaneous contraction of the rat portal vein

  K Shimamura; M Zhou; M Toba; S Kimura; T Higuchi; H Kawaguchi; F Sekiguchi; S Sunano  PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY  446-  (1)  30  -35  2003/04
• Effects of L-arginine on spontaneous contraction of the rat portal vein

  K Shimamura; M Zhou; M Toba; S Kimura; T Higuchi; H Kawaguchi; F Sekiguchi; S Sunano  PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY  446-  (1)  30  -35  2003/04
• Reduced effect of caffeine on twitch contraction of oesophageal striated muscle from stroke-prone spontaneously hypertensive rats

  Fumiko Sekiguchi; Kyoko Kawata; Keiichi Shimamura; Satoru Sunano  Clinical and Experimental Pharmacology and Physiology  30-  (4)  223  -231  2003/04
• Endothelium-dependent relaxation in pulmonary arteries of L-NAME-treated Wistar and stroke-prone spontaneously hypertensive rats

  Fumiko Sekiguchi; Kazuo Yamamoto; Kyoko Matsuda; Kyoko Kawata; Maki Negishi; Kazuaki Shinomiya; Keiichi Shimamura; Satoru Sunano  Journal of Smooth Muscle Research  38-  (4-5)  131  -144  2002/10
• Endothelium-dependent relaxation in pulmonary arteries of L-NAME-treated Wistar and stroke-prone spontaneously hypertensive rats

  Fumiko Sekiguchi; Kazuo Yamamoto; Kyoko Matsuda; Kyoko Kawata; Maki Negishi; Kazuaki Shinomiya; Keiichi Shimamura; Satoru Sunano  Journal of Smooth Muscle Research  38-  (4-5)  131  -144  2002/10
• 25. ラット門脈縦走筋の自発収縮に対するアルギニンの作用について

  木村 真一; 鳥羽 美由起; 周 明; 島村 佳一; 川口 秀明; 関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  6-  (1)  J  -25  2002/04
• 27. 正常血圧と高血圧自然発症ラット大動脈のカフェインによる弛緩反応の比較

  関口 富美子; 三宅 義雅; 樫本 孝史; 砂野 哲  Journal of smooth muscle research. Japanese section  6-  (1)  J  -26  2002/04
• Effects of flufenamic acid on smooth muscle of the carotid artery isolated from spontaneously hypertensive rats

  Keiichi Shimamura; Ming Zhou; Yasuko Ito; Shinichi Kimura; L. B. Zou; Fumiko Sekiguchi; Kenji Kitamura; Satoru Sunano  Journal of Smooth Muscle Research  38-  (1-2)  39  -50  2002/04
• Effects of flufenamic acid on smooth muscle of the carotid artery isolated from spontaneously hypertensive rats

  Keiichi Shimamura; Ming Zhou; Yasuko Ito; Shinichi Kimura; L. B. Zou; Fumiko Sekiguchi; Kenji Kitamura; Satoru Sunano  Journal of Smooth Muscle Research  38-  (1-2)  39  -50  2002/04
• Responses to endothelium-derived factors and their interaction in mesenteric arteries from Wistar-Kyoto and stroke-prone spontaneously hypertensive rats

  F Sekiguchi; T Nakahira; K Kawata; S Sunano  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY  29-  (12)  1066  -1075  2002/12
• Unaltered caffeine-induced relaxation in the aorta of stroke-prone spontaneously hypertensive rats (SHRSP)

  Fumiko Sekiguchi; Yoshimasa Miyake; Takafumi Kashimoto; Satoru Sunano  Journal of Smooth Muscle Research  38-  (1-2)  11  -22  2002/04
• Responses to endothelium-derived factors and their interaction in mesenteric arteries from Wistar-Kyoto and stroke-prone spontaneously hypertensive rats

  F Sekiguchi; T Nakahira; K Kawata; S Sunano  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY  29-  (12)  1066  -1075  2002/12
• Unaltered caffeine-induced relaxation in the aorta of stroke-prone spontaneously hypertensive rats (SHRSP)

  Fumiko Sekiguchi; Yoshimasa Miyake; Takafumi Kashimoto; Satoru Sunano  Journal of Smooth Muscle Research  38-  (1-2)  11  -22  2002/04
• 52. 正常血圧および脳卒中易発症性高血圧自然発症ラットの頸動脈平滑筋におけるベラパミル感受性および非感受性経路を介したカルシウム流入による収縮反応の比較

  関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  5-  (1)  J  -44  2001/04
• 61. 高血圧自然発症ラット胃標本のK^+収縮における内在神経関与の異常

  砂野 哲; 四宮 一昭; 関口 富美子  Journal of smooth muscle research. Japanese section  5-  (1)  J  -49  2001/04
• 14. ラット門脈輪状筋におけるL-アルギニンによる収縮について

  島村 佳一; 木村 真一; 山本 和夫; 関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  5-  (1)  J  -25  2001/04
• Effects of N-G-nitro-L-arginine on the blood pressure of spontaneously hypertensive rats with different degrees of hypertension

  K Yamamoto; K Shimamura; F Sekiguchi; S Sunano  CLINICAL AND EXPERIMENTAL HYPERTENSION  23-  (7)  533  -544  2001/10
• 高血圧自然発症ラットとL-NAME投薬Wistarラットにおける高血圧および（共著）

  近畿大学薬学総合研究所紀要  (10), 33-45-  2001
• 高血圧自然発症ラットの血管における自発性収縮および張力振動と治療効果（共著）

  近畿大学薬学総合研究所紀要  (10), 1-9-  2001
• Rhythmic spontaneous contractions in the rat proximal colon

  S Yoneda; M Kadowaki; S Sugimori; F Sekiguchi; S Sunano; H Fukui; M Takaki  JAPANESE JOURNAL OF PHYSIOLOGY  51-  (6)  717  -723  2001/12
• Hypertension and impairment of endothelium-dependent relaxation of arteries from spontaneously hypertensive and L-NAME-treated wistar rats

  F. Sekiguchi; Y. Miyake; A. Hirakawa; T. Nakahira; M. Yamaoka; K. Shimamura; K. Yamamoto; S. Sunano  Journal of Smooth Muscle Research  37-  (2)  67  -79  2001
• Effects of Ng-nitro-L-arginine on the blood pressure of spontaneously hypertensive rats with different degrees of hypertension

  K. Yamamoto; K. Shimamura; F. Sekiguchi; S. Sunano  Clinical and Experimental Hypertension  23-  (7)  533  -544  2001
• Rhythmic spontaneous contractions in the rat proximal colon

  S Yoneda; M Kadowaki; S Sugimori; F Sekiguchi; S Sunano; H Fukui; M Takaki  JAPANESE JOURNAL OF PHYSIOLOGY  51-  (6)  717  -723  2001/12
• Hypertension and impairment of endothelium-dependent relaxation of arteries from spontaneously hypertensive and L-NAME-treated wistar rats

  F. Sekiguchi; Y. Miyake; A. Hirakawa; T. Nakahira; M. Yamaoka; K. Shimamura; K. Yamamoto; S. Sunano  Journal of Smooth Muscle Research  37-  (2)  67  -79  2001
• Factors involved in the time course of response to acetylcholine in mesenteric arteries from spontaneously hypertensive rats

  S Sunano; T Nakahira; K Kawata; F Sekiguchi  EUROPEAN JOURNAL OF PHARMACOLOGY  423-  (1)  47  -55  2001/06
• Difference in effects of stretch on depressive effect of endothelium-derived nitric oxide on noradrenaline- and high-K+-induced contractions between the aortae from normotensive and spontaneously hypertensive rats

  Fumiko Sekiguchi; Yoshimasa Miyake; Shihoko Nakazumi; Keiichi Shimamura; Kazuo Yamamoto; Satoru Sunano  Journal of Smooth Muscle Research  37-  (1)  9  -23  2001
• Role of nitric oxide in the contraction of circular muscle in the rat portal vein

  K Shimamura; LB Zou; K Matsuda; F Sekiguchi; K Yamamoto; S Sunano  PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY  440-  (3)  435  -439  2000/07
• 6. 高血圧ラットの胃平滑筋におけるイソプロテレノールの弛緩および過分極反応について

  島村 佳一; 山本 和夫; 関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  4-  (1)  J  -19  2000/04
• 大動脈および頸動脈の内皮依存性弛緩に対するSHRSPのペリンドプリル長期治療の効果(共著)

  近畿大学薬学総合研究所紀要  9-  65  -78  2000
• Isoproterenol-induced relaxation in stomach smooth muscle of rats and its abnormality in hypertensive rats.(共著)

  Journal of Muscle Research and Cell Motility  21-  (3)  201  2000
• Transmural field stimulation-induced relaxation in the rat common hepatic artery

  K. Shimamura; K. Yamamoto; F. Sekiguchi; S. Sunano; S. Kimura; H. Saito  Journal of Smooth Muscle Research  36-  (4)  137  -144  2000
• Arterial smooth muscle tone and its modification by endothelium in spontaneously hypertensive rats (共著)

  Biomedical Research  11-  (2)  137  -147  2000
• Altered β-adrenoceptor-mediated responses in the gastric smooth muscle of hypertensive rats

  K. Shimamura; K. Yamamoto; F. Sekiguchi; S. Sunano  Journal of Smooth Muscle Research  36-  (1)  1  -12  2000
• Effect of chronic treatment with perindopril on endothelium-dependent relaxation of aorta and carotid artery in SHRSP

  K. Shimamura; F. Sekiguchi; K. Matsuda; M. Ozaki; K. Noguchi; K. Yamamoto; T. Shibano; M. Tanaka; S. Sunano  Journal of Smooth Muscle Research  36-  (1)  33  -46  2000
• Unaltered endothelium-dependent modulation of contraction in the pulmonary artery of hypertensive rats

  K Matsuda; F Sekiguchi; K Yamamoto; K Shimamura; S Sunano  EUROPEAN JOURNAL OF PHARMACOLOGY  392-  (1-2)  61  -70  2000/03
• P-11. ラット腸間膜動脈平滑筋における内皮依存性弛緩因子, 収縮因子, 過分極因子を介した反応の経時的変化 : 正常血圧ラットと高血圧ラットの比較

  関口 富美子; 中平 智広; 島村 佳一; 砂野 哲  Journal of smooth muscle research. Japanese section  3-  (1)  J  -54  1999/04
• 33. ラット門脈輪状筋標本におけるL-nitroarginineの効果について

  島村 佳一; 鄒 苅波; 松田 恭子; 関口 富美子; 山本 和夫; 砂野 哲  Journal of smooth muscle research. Japanese section  3-  (1)  J  -39  1999/04
• 高血圧ラット大動脈平滑筋の自発性筋緊張調節における内皮由来因子の関与 (共著)

  近畿大学薬学総合研究所紀要  8-  79  -89  1999
• Involvement of endothelium-derived factors in controlling the active tone of smooth muscle in aorta from hypertensive rats (共著)

  Sunano Satoru; Sekiguchi Fumiko  Bulletin of Pharmaceutical Research and Technology Institute  8-  79  -89  1999
• Effects of cyclopiazonic acid on contraction and intracellular Ca2+ in oesophageal striated muscle of normotensive and spontaneously hypertensive rats

  F Sekiguchi; K Shimamura; K Kawata; Y Nakazawa; R Saitoh; Y Yanagitani; S Sunano  BRITISH JOURNAL OF PHARMACOLOGY  128-  (5)  961  -968  1999/11
• Tension oscillation in arteries and its abnormality in hypertensive animals

  K Shimamura; F Sekiguchi; S Sunano  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY  26-  (4)  275  -284  1999/04
• Endothelium-derived relaxing, contracting and hyperpolarizing factors of mesenteric arteries of hypertensive and normotensive rats

  S Sunano; H Watanabe; S Tanaka; F Sekiguchi; K Shimamura  BRITISH JOURNAL OF PHARMACOLOGY  126-  (3)  709  -716  1999/02
• Extracellular Ca2+-dependent contraction by Ca2+ pump inhibition in oesophageal striated muscle of normotensive and hypertensive rats

  F Sekiguchi; K Shimamura; S Sunano  JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY  19-  (4)  449  -450  1998/05
• ラット総肝動脈の非アドレナリン非コリン作動性神経性弛緩について

  島村 佳一; 山本 和夫; 関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  2-  (1)  J  -47  1998/04
• 脳卒中易発症性高血圧自然発症ラット脳底動脈における内皮依存性弛緩の障害

  奥田 広志; 島村 佳一; 山本 和夫; 関口 富美子; 砂野 哲  Journal of smooth muscle research. Japanese section  2-  (1)  J  -58  1998/04
• Membrane potential of mesenteric artery from carvedilol-treated spontaneously hypertensive rats

  K Shimamura; F Sekiguchi; K Matsuda; K Yamamoto; S Tanaka; S Sunano; T Shibutani; H Hashimoto; M Tanaka  EUROPEAN JOURNAL OF PHARMACOLOGY  344-  (2-3)  161  -168  1998/03
• 動脈における内皮依存性および非依存性張力振動と高血庄モデル動物における異常(共著)

  2-  J-99-J-116  1998
• Influences of endothelium on the time course of noradrenaline-, 5-HT-, prostaglandin F(2a)- and high-K+-induced contractions in aortae of WKY and SHRSP

  K. Matsuda; F. Sekiguchi; Y. Miyake; S. Inoue; K. Shimamura; S. Sunano  Journal of Smooth Muscle Research  34-  (5-6)  207  -219  1998
• Involvement of endothelium-derived factors in controlling the active tone of smooth muscle in aorta from hypertensive rats

  F. Sekiguchi; K. Matsuda; K. Shimamura; K. Takeuchi; S. Sunano  Journal of Smooth Muscle Research  34-  (5-6)  221  -232  1998
• Ca2+-sensitivity of portal vein circular muscle from normotensive and hypertensive rats

  K. Shimamura; L. B. Zou; K. Matsuda; K. Yamamoto; F. Sekiguchi; S. Sunano  Journal of Smooth Muscle Research  34-  (1)  23  -34  1998
• Comparison of Reaction in the Preparations of Esophageal Striated Muscle from Hypertensive and Normotensive Rats

  Sunano Satoru; Sekiguchi Fumiko  Bulletin of Pharmaceutical Research and Technology Institute  6-  (6)  29  -36  1997
• HYPERPOLARIZATION AND RELAXATION MEDIATED BY ENDOTHELIUM-DERIVED FACTORS AND ABNORMALITIES IN HYPERTENSIVE ANIMALS

  SUNANO Satoru; SEKIGUCHI Fumiko; MATSUDA Kyoko; SHIMAMURA Keiichi  日本平滑筋学会機関誌  1-  (3)  J-101-J-116  -101-J-116  1997
• 高血圧における血管内皮細胞の役割(共著)

  メディカルレビュー社  1997
• Effects of chronic treatment with carvedilol on smooth muscle tone and endothelium-dependent relaxation of aorta in stroke-prone spontaneously hypertensive rats

  S. Sunano; F. Sekiguchi; A. Nakamura; K. Matsuda; K. Yamamoto; T. Shibutani; H. Hashimoto; M. Tanaka; K. Shimamura  Journal of Smooth Muscle Research  33-  (1)  23  -35  1997
• Comparison of reaction in the preparations of esophageal striated muscle from hypertensive and normotensive rats

  Sunano Satoru; Sekiguchi Fumiko  Bulletin of Pharmaceutical Research and Technology Institute  6-  (6)  29  -36  1997
• Hyperpolarization and relaxation mediated by endothelium-derived factors and abnormalities in hypertensive animals

  SUNANO Satoru; SEKIGUCHI Fumiko; MATSUDA Kyoko; SHIMAMURA Keiichi  J. Smooth Muscle Res. (Japanese Section)  1-  (3)  J-101-J-116  -101-J-116  1997
• Role of endothelial cells in hypertension

  1997
• Effects of amiloride on the neurally mediated contraction of rat mesenteric artery

  K Shimamura; LB Zou; K Moriyama; K Yamamoto; F Sekiguchi; S Sunano  EUROPEAN JOURNAL OF PHARMACOLOGY  320-  (1)  37  -42  1997/02
• Attenuation of intrinsic active tone by endothelium-derived nitric oxide in aortae of spontaneously hypertensive rats with different levels of blood pressure

  S Sunano; F Sekiguchi; K Takeuchi; S Shibutani; K Matsuda; K Shimamura  CLINICAL AND EXPERIMENTAL HYPERTENSION  18-  (6)  873  -890  1996/08
• Endothelium-Dependent relaxation by alpha(2)-adrenoceptor agonists in spontaneously hypertensive rat aorta

  S Sunano; LB Zou; K Matsuda; F Sekiguchi; H Watanabe; K Shimamura  JOURNAL OF CARDIOVASCULAR PHARMACOLOGY  27-  (5)  733  -739  1996/05
• Blood pressure and age-dependent changes of endothelium-dependent tension oscillations in different strains of spontaneously hypertensive rats

  K. Shimamura; K. Matsuda; F. Sekiguchi; S. Sunano  Journal of Smooth Muscle Research  32-  (4)  145  -154  1996
• Spontaneous and agonist-induced contractions and endothelium-dependent relaxation in aortae from SHRSP and WKY rats under various levels of passive force

  F Sekiguchi; T Adachi; H Matsubara; K Matsuda; K Kita; K Shimamura; S Sunano  CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY  23-  (6-7)  483  -489  1996/06
• Effects of cyclopiazonic acid and thapsigargin on electromechanical activities and intracellular Ca2+ in smooth muscle of carotid artery of hypertensive rats

  F Sekiguchi; K Shimamura; M Akashi; S Sunano  BRITISH JOURNAL OF PHARMACOLOGY  118-  (4)  857  -864  1996/06
• <血行動態に関する研究>高血圧ラット胸部大動脈平滑筋の自発性筋緊張と膜電位について

  砂野 哲; 島村 佳一; 山本 和夫; 関口 富美子  近畿大学医学雑誌  20-  (2)  29  -31  1995/12
• Effects of N(G)-nitro-L-arginine on α-agonists induced contraction of aortae from Wistar Kyoto rats and stroke-prone spontaneously hypertensive rats

  K. Matsuda; F. Sekiguchi; M. Tojo; K. Shimamura; S. Sunano  Journal of Smooth Muscle Research  31-  (2)  51  -60  1995
• Involvement of arachidonic acid cascade products in noradrenaline-induced contraction of the aorta from WKY and SHRSP

  SUNANO Satoru; MATSUDA Kyoko; YAMAMOTO Kazuo; SASAKI Fumiko; SHIMAMURA Keiichi  Medical journal of Kinki University  19-  (4)  39  -41  1994/12
• Comparison of endothelium-dependent and -independent tension oscillation in aortae of stroke-prone spontaneously hypertensive rats and Wistar Kyoto rats

  S. Sunano; F. Sasaki; S. Osugi; K. Shimamura  Journal of Smooth Muscle Research  30-  (4)  135  -145  1994
• Roles of extra- and intracellular Ca in aortic smooth muscle tone of spontaneously hypertensive rats (共著)

  Journal of Muscle Research and Cell Motility  14-  (3)  373  1994
• CA2+-DEPENDENT ACTIVE TONE AND BLOOD-PRESSURE IN VARIOUS SPONTANEOUSLY HYPERTENSIVE RATS

  S SUNANO; F SASAKI; K SHIMAMURA  JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY  15-  (3)  362  -363  1994/06
• 血管平滑筋収縮の内皮による調節と高血圧自然発症ラットの血管における異常(共著)

  近畿大医誌  18-  65  -67  1993
• Elevation of spontaneous tone and effects of antihypertensive treatments in arterial smooth muscle of spontaneously hypertensive rats

  S. Sunano; F. Sasaki  Journal of Smooth Muscle Research  29-  (4)  111  -130  1993
• Relationship between blood pressure and smooth muscle tone in aortae of hypertensive rats: Roles of (Ca2+)

  Fumiko Sasaki; S. Osugi; K. Shimamura; S. Sunano  Journal of Smooth Muscle Research  29-  (3)  69  -79  1993
• Effects of endothelium- and smooth muscle-derived nitric oxide and arachidonic acid metabolites on norepinephrine-induced contraction of rat aorta (共著)

  Alpha-Adrenoceptor  254-257-  1992
• Reduced effect of caffeine on twitch contraction of esophageal striated muscle from SHRSP （共著）

  Clinical and Experimental Pharmacology and Physiology
• 高血圧ラット胸部大動脈平滑筋の自発性筋緊張と膜電位

  近畿大医誌  20-  (2、29-31)
• Sopntaneous tone and membrene potenitial in the aortic smooth muscle from hypertensive rats (共著)

  med.J.Kinki Univ.  20-  (2、29-31)
• 肝障害はボルテゾミブ誘発性末梢神経障害の発症リスクを増大させる

  宮本朋佳; 宮本朋佳; 富士谷昌典; 堂本莉紗; 畑中重克; 福山紘基; 関口富美子; 小泉祐一; 川畑篤史  日本薬理学雑誌  154-  (Supplement)  2019
• マウスにおいて肝障害により放出されるHMGB1はボルテゾミブ誘発性末梢神経障害を増悪させる。

  堂本莉紗; 宮本朋佳; 宮本朋佳; 関口富美子; 坪田真帆; 小泉祐一; 西堀正洋; 川畑篤史  日本薬理学雑誌  154-  (Supplement)  2019
• マウスにおけるCa_v3.2T型Ca²⁺チャネルを介する硫化水素の痛み促進効果はアスコルビン酸欠乏により増大する:SMP30/GNLノックアウトマウスを用いた検討

  上坊健太; 三木好輝; 坪田真帆; 関口富美子; 近藤嘉高; 高橋経太; 増富裕文; 石神昭人; 川畑篤史  生体機能と創薬シンポジウム要旨集  2013-  2013
• Ca_v3.2T型Ca²⁺チャネルを阻害するascorbic acidの欠乏は硫化水素による体性痛・内臓痛およびpaclitaxel誘起神経障害性疼痛を増強する

  上坊健太; 三木好輝; 坪田真帆; 関口富美子; 近藤嘉高; 高橋経太; 増富裕文; 石神昭人; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  125th-  2014
• Ascorbic acid欠乏は,Ca_v3.2T型Ca²⁺チャネルを介する痛みを増強する

  坪田真帆; 上坊健太; 三木好輝; 福田亮太郎; 関口富美子; 近藤嘉高; 高橋経太; 増富裕文; 石神昭人; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2015-  2015
• The Potent iNOS Inhibitor ONO-1714 inhibits nNOS and exerts Antinociception

  Sekiguchi Fumiko; Mita Yoko; Kamanaka Yoshihisa  Bulletin of Pharmaceutical Research and Technology Institute  13-  91  -101  2005/03
• マクロファージ由来HMGB1の炎症性痛覚過敏への関与と分子作用メカニズムの解析

  山岨大智; 関由加里; 山西広樹; 坪田真帆; 関口富美子; 八木秀樹; 益子高; 西堀正洋; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  126th-  2014
• 末梢組織中HMGB1により誘起される痛覚過敏のメカニズム:上流および下流シグナルの解析

  山岨大智; 関由加里; 山西広樹; 坪田真帆; 関口富美子; 西堀正洋; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2014-  2014
• マウスにおけるlipopolysaccharide誘起炎症性痛覚過敏および抗癌剤paclitaxel誘起神経障害性疼痛へのマクロファージ由来high mobility group box 1の関与

  堂本莉紗; 山岨大智; 山西広樹; 関口富美子; 坪田真帆; 西堀正洋; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2015-  2015
• マクロファージ由来high mobility group box1はマウスにおけるlipopolysaccharide誘起炎症性痛覚過敏及び抗癌剤paclitaxel誘起神経障害性疼痛に関与する

  堂本莉紗; 山岨大智; 山西広樹; 関口富美子; 坪田真帆; 西堀正洋; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  128th-  2015
• マクロファージ由来HMGB1はlipopolysaccharide誘起炎症性疼痛とpaclitaxel誘起神経障害性疼痛に関与する

  堂本莉紗; 山岨大智; 山西広樹; 関口富美子; 坪田真帆; 西堀正洋; 川畑篤史  Pain Research  31-  (2)  2016
• Bortezomib誘起神経障害性疼痛への核内タンパクhigh mobility group box1の関与

  宮崎貴也; 坪田真帆; 冨田詩織; 出口智代; 関口富美子; 山岨大智; 西堀正洋; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  130th-  2016
• Effects of curcumin on PAR2-triggered prostaglandin E-2 production in human alveolar epithelial A549 cells

  Kazumi Moriyuki; Kaori Matsubara; Fumiko Sekiguchi; Hiroyuki Nishikawa; Atsufurni Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  106-  210P  -210P  2008
• Neurite outgrowth and functional up-regulation of voltage-dependent calcium channels caused by cyclic AMP in sensory neuron-like cells

  K. Mitani; Y. Tanaka; F. Sekiguchi; S. Yoshida; A. Kawabata  EUROPEAN JOURNAL OF NEUROLOGY  16-  86  -86  2009/10
• The delayed release of PGE(2) mediated by PAR1 involves slowly developing production of arachidonic acid in rat gastric mucosal epithelial cells

  Yuma Maeda; Fumiko Sekiguchi; Ai Ohi; Kaori Takaoka; Hiroyuki Nishikawa; Atsufumi Kawabata  FASEB JOURNAL  23-  2009/04
• Characterization of H2S-induced neuronal death in cultured cortical neurons: involvement of the MEK/ERK pathway

  Yuko Kurokawa; Satoko Kubo; Yoshiko Yamasaki; Fumiko Sekiguchi; Yukari Okamoto; Yuma Maeda; Toshiaki Kume; Nobuyuki Fukushima; Akinori Akaike; Atsuhumi Kawadata  JOURNAL OF PHARMACOLOGICAL SCIENCES  109-  189P  -189P  2009
• Relationship between expression of PARs and infection with H. pylori in the stomach of gastric cancer patients

  Kazuki Fukami; Fumiko Sekiguchi; Kaori Takaoka; Kensaku Miyake; Takatsugu Yamamoto; Shogo Tanaka; Kohichi Ohno; Hiroyasu Ishikura; Mitsuhide Naruse; Atsufumi Kawabata  FASEB JOURNAL  23-  2009/04
• THE TIME LAG OF PGE(2) RELEASE AND COX-2 UP-REGULATION TRIGGERED BY PAR1 IS DUE TO DEFICIENCY OF ARACHIDONIC ACID IN GASTRIC EPITHELIAL CELLS

  Fumiko Sekiguchi; Yuma Maeda; Ai Ohi; Kaori Takaoka; Hiroyuki Nishikawa; Atsufumi Kawabata  JOURNAL OF PHYSIOLOGICAL SCIENCES  59-  430  -430  2009
• A critical role for Ca(v)3.2 T-type calcium channels targeted by endogenous hydrogen sulfide in the maintenance of neuropathic pain

  Tomoko Takahashi; Kenji Mitani; Motohide Takemura; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  109-  190P  -190P  2009
• Hydrogen sulfide induces neuronal differentiation via sensitization of Ca(v)3.2 T-type calcium channels followed by activation of Src family tyrosine kinase in NG108-15 cells

  Takeshi Tarui; Kazuki Fukami; Keita Nagasawa; Shigeru Yoshida; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  109-  158P  -158P  2009
• EFFECT OF HELICOBACTER PYLORI EXTRACTS ON PROSTAGLANDIN E-2 PRODUCTION IN HUMAN LUNG ALVEOLAR EPITHELIAL A549 CELLS

  Yuma Maeda; Fumiko Sekiguchi; Yuki Matsumoto; Hiroyuki Nishikawa; Atsufumi Kawabata  JOURNAL OF PHYSIOLOGICAL SCIENCES  59-  431  -431  2009
• IL-8 release triggered by proteinase-activated receptor-2 stimulation involves both MEK/ERK and PI3 kinase/Akt pathways in gastrointestinal epithelial cells

  Fumiko Sekiguchi; Yusuke Tanaka; Hao Hong; Atsufumi Kawabata  FASEB JOURNAL  23-  2009/04
• Characterization of cyclic AMP-dependent neurite outgrowth and enhancement of ion channel functions in ND7/23 cells derived from rat dorsal root ganglion

  Kenji Mitani; Yukari Tanaka; Fumiko Sekiguchi; Shigeru Yoshida; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  112-  235P  -235P  2010
• Involvement of T-type calcium channels in hyperalgesia induced by cyclic AMP

  Yuka Aoki; Maiko Nakagawa; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  112-  115P  -115P  2010
• Roles of proteinases, proteinase-activated receptor-2 and transient receptor potential vanilloid-1 channels in processing of pancreatic pain

  Sachiyo Nishimura; Hiroyasu Ishikura; Maho Matsunami; Yui Shinozaki; Fumiko Sekiguchi; Mitsuhide Naruse; Taisuke Kitamura; Ryukichi Akashi; Kenji Matsumura; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  112-  114P  -114P  2010
• Role of hydrogen sulfide as a novel endogenous nociceptive messenger

  T Ishiki; Y Maeda; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  87P  -87P  2006
• Protective role of the endogenous gasomessenger hydrogen sulfide in rat gastric mucosa

  D Yonezawa; M Miyamoto; E Taniguchi; M Honjo; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  161P  -161P  2006
• Antinociceptive effect of camostat mesilate on pancreatitis-related pain in rodents

  S Nishimura; H Ishikura; M Matsunami; T Tsujiuchi; F Sekiguchi; N Naruse; T Nakatani; Y Kamanaka; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  156P  -156P  2006
• PAR2 signaling for production of IL-8 and prostaglandin E-2 in human lung epithelial cells

  M Nagataki; K Moriyuki; F Sekiguchi; H Nishikawa; H Araki; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  234P  -234P  2006
• Hydrogen sulfide, a novel endogenous gasomessenger, causes relaxation in mouse bronchial smooth muscle

  Doe, I; S Kubo; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  235P  -235P  2006
• Effect of hydrogen sulfide, a gaso-messenger, on gastric vascular tension and mucosal circulation in rats

  S Kubo; M Kajiwara; Doe, I; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  100-  162P  -162P  2006
• Prostaglandin E-2 production triggered by proteinaseactivated receptor-1 in rat gastric mucosal epithelial cells: Cell signaling and modulation by peroxisome proliferatoractivated receptor-gamma ligands

  K. Takaoka; F. Sekiguchi; S. Saito; H. Hayashi; M. Nagataki; H. Nishikawa; A. Kawabata  REGULATORY PEPTIDES  135-  (3)  199  -200  2006/08
• Correlation of enzymes responsible for generation and detoxification of hydrogen sulfide with inflammatory bowel disease (IBD) in rodents

  Eiichi Taniguchi; Daiki Yonezawa; Tsuyoshi Isiki; Maho Matsunami; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  103-  66P  -66P  2007
• Involvement of the gas messenger hydrogen sulfide in pancreatic pain

  Osamu Fukushima; Sachiyo Nishimura; Hiroyasu Ishikura; Tomoko Takahashi; Maho Matsunami; Fumiko Sekiguchi; Mitsuhide Naruse; Yoshihisa Kamanaka; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  103-  66P  -66P  2007
• Cellular signaling and induction of cyclooxygenase-2 caused by proteinase-activated receptor-2 (PAR-2) activation in human lung epithelial cells

  M Nagataki; N Kawao; K Nagasawa; K Cushing; F Sekiguchi; WK MacNauguton; MD Hollenberg; H Nishikawa; H Araki; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  227P  -227P  2005
• The potent PAR-2 agonist 2-furoly-LIGRL-amide is a powerful and orally available gastric mucosal protective agent

  D Yonezawa; Y Oono; N Inoi; M Honjo; M Hirofuchi; F Sekiguchi; M Iwaki; T Kanke; H Ishiwata; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  198P  -198P  2005
• Roles for hydrogen sulfide, a novel endogenous gasomessenger, in modulation of the motility in isolated rat arterial tissues

  S Kubo; Doe, I; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  87P  -87P  2005
• PAR-1 pepducins (intracellular agonist and antagonist): Distinct activity in multiple cells/tissues

  T Ishiki; S Kubo; Doe, I; F Sekiguchi; M Nagataki; H Nishikawa; M Tanaka; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  244P  -244P  2005
• Intracellular signaling for prostaglandin E-2 production caused by activation of the thrombin receptor, PAR-1, in the rat gastric mucosal epithelial cells

  F Sekiguchi; S Saito; M Nagataki; N Kawao; H Nishikawa; H Araki; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  108P  -108P  2005
• Modulation of visceral pain by PAR-2: antinociceptive/protective roles during pancreatitis and involvement in delayed colonic hyperalgesia

  A Kawabata; M Matsunami; N Kawao; T Kitano; M Tsutsumi; T Ishiki; R Satoh; F Sekiguchi; T Minami; T Kanke  JOURNAL OF PHARMACOLOGICAL SCIENCES  97-  197P  -197P  2005
• Endogenous hydrogen sulfide contributes to cell proliferation in gastric cancer cells

  Fumiko Sekiguchi; Teruki Sekimoto; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  118-  122P  -122P  2012
• Molecular mechanisms for the neurite outgrowth through the prostaglandin E-2/cyclic AMP pathway in mouse dorsal root ganglion cells

  Takashi Maeda; Kenji Mitani; Ryosuke Yamagata; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  118-  182P  -182P  2012
• Study on molecular mechanisms for interstitial cystitis using a substance P-induced delayed bladder pain model in mice: roles of endogenous hydrogen sulfide and Ca(v)3.2 T-type Ca2+ channels

  Maho Matsunami; Yasumasa Okawa; Kazumasa Okubo; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  118-  193P  -193P  2012
• The effects of ryanodine on twitch contraction in the esophageal striated muscle of rats - Comparison between the preparations from normotensive and spontaneously hypertensive rats

  F Sekiguchi; M Yamazoe; S Sunano  JAPANESE JOURNAL OF PHARMACOLOGY  88-  100P  -100P  2002
• Effects of ryanodine on high-K+-induced contracture in the esophageal striated muscle and difference between the preparations from normotensive and spontaneously hypertensive rats

  S Sunano; M Shiba; F Sekiguchi  JAPANESE JOURNAL OF PHARMACOLOGY  88-  100P  -100P  2002
• Impaired endothelium-dependent relaxation in aorta from stroke-prone spontaneously hypertensive rats and in aorta from Wistar Kyoto rats in the presence of L-nitroarginine are.improved by superoxide dismutase.

  S Sunano; A Yanamoto; F Sekiguchi  JOURNAL OF PHARMACOLOGICAL SCIENCES  91-  268P  -268P  2003
• Differences of response in esophageal striated muscles between Wistar Kyoto rats and stroke-prone spontaneously hypertensive rats are independent of age and blood pressure.

  F Sekiguchi; M Ueta; K Suzuki; S Sunano  JOURNAL OF PHARMACOLOGICAL SCIENCES  91-  101P  -101P  2003
• Effect, of Mn(III) tetrakis[1-methyl-4-pyridyl]porphyrin (MnTMPyP) on carotid artery of normotensive Wistar Kyoto rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP).

  S Sunano; M Seo; F Sekiguchi  JOURNAL OF PHARMACOLOGICAL SCIENCES  91-  267P  -267P  2003
• L-arginine increased the frequency of spontaneous contraction in rat portal vein.

  S Kimura; M Zhou; M Toba; K Shimamura; H Kawaguchi; F Sekiguchi; S Sunano  JOURNAL OF PHARMACOLOGICAL SCIENCES  91-  262P  -262P  2003
• Mechanisms for relaxation caused by PAR-2 and PAR-1 activation in mouse airway smooth muscle

  S Kubo; T Ishiki; N Kawao; F Sekiguchi; R Kuroda; N Saito; Y Hattori; MD Hollenebrg; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  94-  249P  -249P  2004
• The bisphosphonate drug etidronate suppresses allodynia via ATP-sensitive K+ channels in adjuvant-arthritic rats

  N Kawao; Y Hironaka; R Kuroda; F Sekiguchi; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  94-  117P  -117P  2004
• Mechanisms for modulation of mouse gastrointestinal motility caused by protease-activated receptor (PAR)-1 and PAR-2 activation

  F Sekiguchi; N Hasegawa; D Yonezawa; N Inoi; T Kanke; N Saito; A Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  94-  257P  -257P  2004
• Endogenous H2S augments secretory functions via activation of Ca(v)3.2 T-type Ca2+ channels in neuroendocrine-differentiated prostate cancer cells

  Kazuki Fukami; Ryuji Kasamatsu; Shigeru Yoshida; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  115-  92P  -92P  2011
• Therapeutic effect of RQ-00311651, a novel T-type Ca2+. channel blocker, on distinct visceral pain

  Eri Kawakami; Maho Tsubota-Matsunami; Tomoka Ozaki; Fumiko Sekiguchi; Tadashi Inoue; Takako Okumura; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  121-  225P  -225P  2013
• RQ-00311651, a novel T-type calcium channel blocker: the inhibitory effects on membrane currents or calcium influx, and analgesic activity

  Yuma Kawara; Fumiko Sekiguchi; Daiki Kanaoka; Yudai Kawaishi; Maho Tsubota-Matsunami; Shigeru Yoshida; Tsuyako Ohkubo; Mio Yamasawa; Norikazu Gaja; Hiroyuki Ohshiro; Tadashi Inoue; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  121-  224P  -224P  2013
• Recombinant human soluble thrombomodulin suppresses bladder pain in mice with cyclophosphamide-induced cystitis

  Kaoru Yamaguchi; Junichi Tanaka; Yukari Seki; Hiroyasu Ishikura; Maho Tsubota-Matsunami; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  121-  225P  -225P  2013
• Recombinant human soluble thrombomodulin abolishes HMGB1-dependent inflammatory hyperalgesia in rats

  Yukari Seki; Junichi Tanaka; Kaoru Yamaguchi; Hiroyasu Ishikura; Maho Tsubota-Matsunami; Fumiko Sekiguchi; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  121-  225P  -225P  2013
• Contraction induced by cyclopiazonic acid of thapsigargin on the carotid artery of rats: Comparison between carotid arterial smooth muscle from normotensive rats and that from hypertensive rats

  F Sekiguchi; K Shimamura; S Sunano  JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY  17-  (2)  294  -294  1996/04
• Tacrolimus, a calcineurin inhibitor, potentiates capsaicin-evoked colonic pain in mice

  Yuka Terada; Maho Tsubota; Fumiko Sekiguchi; Kyoichi Wada; Takeshi Kuwahara; Mitsutaka Takada; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  124-  185P  -185P  2014
• Preventive or therapeutic effects of anti-HMGB1 neutralizing antibody and recombinant human soluble thrombomodulin in rats with neuropathy induced by vincristine

  Takeshi Nishida; Yudai Kawaishi; Hiroki Yamanishi; Maho Tsubota; Fumiko Sekiguchi; Hiroyasu Ishikura; Masahiro Nishibori; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  124-  101P  -101P  2014
• Ascorbic acid deficiency augments hyperalgesia induced by hydrogen sulfide in mice

  Maho Tsubota; Kenta Uebo; Koki Miki; Fumiko Sekiguchi; Yoshitaka Kondo; Keita Takahashi; Hirofumi Masutomi; Akihito Ishigami; Atsufumi Kawabata  NITRIC OXIDE-BIOLOGY AND CHEMISTRY  39-  S29  -S29  2014/05
• Involvement of endogenous hydrogen sulfide and T-type calcium channels in cyclic AMP-induced neuronal differentiation in ng108-15 cells

  Fumiko Sekiguchi; Yuki Takeda; Daiki Kanaoka; Shigeru Yoshida; Atsufumi Kawabata  NITRIC OXIDE-BIOLOGY AND CHEMISTRY  39-  S37  -S37  2014/05
• Inactivation of HMGB1 with its neutralizaing antibody and recombinant human soluble thrombomodulin suppresses paclitaxel-induced neuropathy in rats and mice

  Yudai Kawaishi; Hiroki Yamanishi; Maho Tsubota; Fumiko Sekiguchi; Takeshi Nishida; Hiroyasu Ishikura; Masahiro Nishibori; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  124-  154P  -154P  2014
• Involvement of T-type Ca2+ channels in the novel cognitive enhancer ST101-induced facilitation of neurite outgrowth in NG108-15 cells and hyperalgesia in mice

  Sumire Ohno; Daiki Kanaoka; Hiroki Ide; Fumiko Sekiguchi; Shigeru Yoshida; Kohji Fukunaga; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  124-  154P  -154P  2014
• T-type Ca2+ channel inhibiting activity and anti-hyperalgesic effect of SOPHORAE RADIX-derived sophoraflavanone G and its analogues

  Fumiko Sekiguchi; Tomoyo Fujita; Takahiro Deguchi; Maki Ichii; Hiroyuki Nishikawa; Shigeru Yoshida; Kazuya Murata; Hideaki Matsuda; Tsuyako Ohkubo; Atsufumi Kawabata  JOURNAL OF PHARMACOLOGICAL SCIENCES  124-  185P  -185P  2014
• プロテアソーム阻害作用を有する多発性骨髄腫治療薬bortezomibによって誘起されるマウスの神経障害性疼痛には一次知覚神経におけるCav3.2T型Ca2+チャネルの発現量増加が関与する

  関口 富美子; 冨田 詩織; 出口 智代; 坪田 真帆; 吉田 繁; 川畑 篤史  日本生物学的精神医学会・日本神経精神薬理学会合同年会プログラム・抄録集  39回・47回-  187  -187  2017/09
• 急性および慢性術後痛におけるHMGB1の役割

  川端 柚希; 林 愛理沙; 坪田 真帆; 中武 ゆい; 辻田 隆一; 関口 富美子; 西堀 正洋; 川畑 篤史  PAIN RESEARCH  33-  (2)  139  -139  2018/06
• 中分子ヘパリニルフェニルアラニンは化学療法誘起末梢神経障害を抑制する

  西川 裕之; 上野山 桐子; 関口 富美子; 坪田 真帆; 岡田 卓哉; 豊岡 尚樹; 川畑 篤史  PAIN RESEARCH  33-  (2)  156  -156  2018/06
• RAGEを標的とした化学療法誘起末梢神経障害治療薬の探索 in silicoドラッグ・リプロファイリング/リポジショニングからのアプローチ

  脇谷 航平; 関口 富美子; 坪田 真帆; 中村 真也; 仲西 功; 川畑 篤史  PAIN RESEARCH  33-  (2)  157  -157  2018/06
• オキサリプラチン誘起神経障害性疼痛の発症メカニズムの解析:Ca_v3.2 T型カルシウムチャネルとHMGB1の関与

  坪田真帆; 福田亮太郎; 関口富美子; 宮崎貴也; 堂本莉紗; 安井洋樹; 山下莉加; 上田慎; 西田武司; 西田武司; 石倉宏恭; 西堀正洋; 川畑篤史  Pain Research  32-  (2)  131  2017/06
• プロテアソーム阻害薬bortezomib誘起神経障害性疼痛には一次知覚神経のCa_v3.2T型カルシウムチャネルタンパク量増加が関与する

  関口富美子; 冨田詩織; 出口智代; 坪田真帆; 吉田繁; 川畑篤史  Pain Research  32-  (2)  154  2017/06
• マウスにおいてHMGB1足底内投与により誘起される機械的アロディニアにはNF‐κBシグナルとマクロファージが関与する

  堂本莉紗; 中島夏奈; 関口富美子; 坪田真帆; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2017-  57  2017/08
• Butyrate誘起過敏性腸症候群モデルマウスにおける結腸痛へのマクロファージ由来HMGB1の関与

  坪田真帆; 梶谷梨絵; 野中結; 石井優子; 関口富美子; 西堀正洋; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2017-  46  2017/08
• Bortezomib誘起神経障害性疼痛へのマクロファージ由来HMGB1の関与

  宮崎貴也; 坪田真帆; 冨田詩織; 出口智代; 関口富美子; 西堀正洋; 川畑篤史  次世代を担う創薬・医療薬理シンポジウムプログラム・要旨集  2017-  63  2017/08
• AzelastineはRAGEが関与する化学療法誘起末梢神経障害の発症を抑制する―ドラッグ・リプロファイリング/リポジショニング研究からの知見

  脇谷航平; 関口富美子; 坪田真帆; 中村真也; 仲西功; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  133rd-  44  2018
• T型Ca²⁺チャネル阻害活性を有するホップ成分6‐prenylnaringeninは結腸痛を抑制する

  坪田真帆; 松井和樹; 中野真希; 友近拳; 関口富美子; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  133rd-  34  2018
• がん化学療法誘起末梢神経障害モデルマウスにおける中分子ヘパリニルフェニルアラニンの抗アロディニア作用

  西川裕之; 西川裕之; 上野山桐子; 関口富美子; 坪田真帆; 岡田卓哉; 豊岡尚樹; 豊岡尚樹; 川畑篤史  日本薬理学会近畿部会プログラム・要旨集  133rd-  33  2018

Industrial Property Rights

• WO2014-188980:T型カルシウムチャネル阻害剤  2014/11/27

  川畑 篤史, 松田 秀秋, 関口 富美子, 村田 和也, 西川 裕之  学校法人近畿大学, 扶桑薬品工業株式会社  201703002436644001

Awards & Honors

• 2019/10 6th Congress of AsCNP Excellent Presentation Award for AsCNP2019, Category: Senior Researcher
   Paclitaxel, an anti-cancer drug, causes extracellular release of HMGB1, a pro-inflammatory and pro-nociceptive mediator, in Schwann cells derived from neonatal rat sciatic nerves. 

  受賞者: Fumiko Sekiguchi
• 平成16（2004）年度 日本薬学会近畿支部奨励賞
  

Research Grants & Projects

• 血栓止血系分子とHMGB1の相互干渉による疼痛制御のメカニズムと臨床的意義の解明

  日本学術振興会：科学研究費助成事業 基盤研究(C)

  Date (from‐to) : 2021/04 -2024/03 

  Author : 川畑 篤史; 関口 富美子; 坪田 真帆
• 内因性硫化水素合成阻害による抗がん剤の有効性増大と副作用軽減の可能性について

  日本学術振興会：科学研究費助成事業 基盤研究(C)

  Date (from‐to) : 2020/04 -2023/03 

  Author : 関口 富美子; 川畑 篤史; 坪田 真帆

   

  本研究課題では、生体内で数種の合成酵素により産生される硫化水素（H2S）が、抗がん剤による化学療法誘起末梢神経障害（CIPN）の発症および抗がん剤抵抗性獲得に寄与するかを検討することを目的としている。実際に、抗がん剤によるCIPN発症と治療効果の減弱に内因性H2Sの寄与が明らかとなれば、H2S合成酵素阻害薬が抗がん剤との併用投与により、副作用であるCIPNの軽減と抗がん剤の治療効果増大の両面において高い有用性を示すことが期待できる。2020年度は、ヒト多発性骨髄腫（multiple myeloma, MM）由来KMS-11細胞と、MMの治療に使用される抗がん剤ボルテゾミブ（BTZ）に対して耐性を獲得したKMS-11/BTZ細胞を用いて、BTZ非存在下あるいは存在下における細胞増殖におよぼす内因性H2Sの関与について検討を行った。その結果、BTZ非存在下、存在下どちらにおいても、KMS-11およびKMS-11/BTZの細胞増殖はH2S合成酵素のcystathionine-β-synthase（CBS）の阻害薬により顕著に、cystathionine-γ-lyase（CSE）阻害薬により部分的に抑制されたが、CSE阻害薬の効果はKMS-11細胞で小さかった。これら阻害薬による増殖抑制効果はH2S供与体のNa2SあるいはGYY4137により一部減弱した。一方、別のH2S合成酵素である3-mercaptopyruvate sulfur transferase（3-MST）の阻害薬はこれら細胞の増殖にほとんど影響しなかった。これらの結果より、KMS-11およびKMS-11/BTZ細胞の増殖は内因性H2Sにより促進的に調節されており、その産生には主にCBSが寄与していることが示唆された。
• Novel therapeutic strategy targeting RAGE for treatment of peripheral neuropathy and visceral pain

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

  Date (from‐to) : 2017/04 -2020/03 

  Author : Kawabata Atsufumi, Sekiguchi Fumiko, Tsubota Maho

   

  To develop seeds for development of medicines targeting RAGE for treatment of intractable pain, the present study first ascertained the involvement of RAGE in neuropathic and visceral pain using animal models. We then demonstrated that middle-molecular-weight-heparinylphenylalanine suppressed intractable pain possibly through selective blockade of RAGE. Our in silico analysis identified a small molecule compound that inhibits AGE-RAGE binding and is useful as a seed compound for novel RAGE blocker development. Together, our study identified both large and small molecules as RAGE blockers, which would be useful for pain treatment.
• Study on the role of nuclear protein HMGB1 in the process of neurite regeneration after nerve injury

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2017/04 -2020/03 

  Author : SEKIGUCHI Fumiko
• Study on the physiological role of endogenous hydrogen sulfide in the stomach with mucosal injury

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2014/04 -2017/03 

  Author : SEKIGUCHI Fumiko
• Involvement of T-type calcium channels and calcineurin in the inflammatory and neuropathic pain

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2011/04 -2014/03 

  Author : SEKIGUCHI Fumiko
• Effects of Helicobacter pylori on expression levels and function of proteinase-activated receptors in the gastric mucosal epithelial cells

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2008/04 -2011/03 

  Author : SEKIGUCHI Fumiko
• Involvement of the gasotransmitter hydrogen sulfide in neurogenic pain

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

  Date (from‐to) : 2008 -2010 

  Author : KAWABATA Atsufumi; YOSHIDA Shigeru; SEKIGUCHI Fumiko

   

  We first demonstrated the involvement of Cav3.2 T-type calcium channels in hydrogen sulfide-induced facilitation of nociception. We then found that, in rats with L5 spinal nerve injury, the activation of Cav3.2 by endogenous hydrogen sulfide was involved in the maintenance of hyperalgesia/allodynia, and Cav3.2 was upregulated, suggesting that the hydrogen sulfide/Cav3.2 pathway should be a therapeutic target for treatment of neurogenic pain.
• Roles for hydrogen sulfide, a novel endogenous gasotransmitter, in nociceptive processing

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

  Date (from‐to) : 2005 -2007 

  Author : KAWABATA Atsufumi; SEKIGUCHI Fumiko; YOSHIDA Shigeru

   

  We investigated roles for hydrogen sulfide, a possible novel gasotransmitter, in nociceptive processing, and obtained the following results : 1) Hyperalgesia caused by administration of hydrogen sulfide and L-cysteine We first found that intraplantar (i.pl.) administration of NaHS, a donor for hydrogen sulfide, caused mechanical hyperalgesia in rats, an effect being mediated by activation of T-type calcium channels. Similarly, L-cysteine, an endogenous origin of hydrogen sulfide, when administered i.pl., produced hyperalgesia. This effect was considered to be mediated by production of endogenous hydrogen sulfide by cystathionine-gamma-lyase (CSE) from L-cysteine. The hyperalgesic effect of the hydrogen sulfide donor was accompanied by expression of Fos protein in the superficial layers of the spinal dorsal horn. 2) Facilitation by hydrogen sulfide of T-type calcium channel-mediated membrane currents in NG108-15 cells and mouse spinal dorsal root ganglion (DRG) neurons We examined effect of hydrogen sulfide on functions of T-type calcium channels by determining barium currents using the whole-cell-patch-clamp method, and found that hydrogen sulfide facilitated T-type calcium channel-mediated membrane currents on NG108-15 cells and mouse DRG neurons. 3) Visceral pain caused by colonic luminal hydrogen sulfide in mice Intracolonic administration of NaHS, a donor it hydrogen sulfide, caused visceral pain-like nociceptive behavior and referred abdominal hyperalgesia in mice, accompanied by phosphorylation of ERK in nociceptive neurons present in the superficial layers of the spinal dorsal horn. Together, our study strongly suggests that endogenous hydrogen sulfide plays a role as a novel messenger in nociceptive processing.
• Study on mechanisms for modulation of gastrointestinal motility by G-protein-coupled proteinase-activated receptors

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2004/04 -2006/03 

  Author : SEKIGUCHI Fumiko
• 高血圧ラットの血管平滑筋の緊張と細胞内カルシウム

  Date (from‐to) : 1991 -2003
• Tone and intercellular Ca in the vascular smooth muscle of hypertensive rats

  Date (from‐to) : 1991 -2003
• プロテアーゼ活性化受容体の生理および病態生理学的役割の検討

  Date (from‐to) : 2003
• Study on physiological and pathophysilogical roles of protease-activated receptor.

  Date (from‐to) : 2003

Teaching Experience

Neuropharmacology and NeuropathophysiologyNeuropharmacology and Neuropathophysiology

Other link

researchmap

https://researchmap.jp/Fumiko_Sekiguchi