2001 Fiscal Year Annual Research Report

血管攣縮の分子機構:平滑筋Ca感受性亢進に関与する細胞内情報伝達網の解明

Research Project

Project/Area Number	13470149
Research Institution	Kyushu University
Principal Investigator	金出英夫九州大学, 大学院・医学研究院, 教授 (80038851)
Co-Investigator(Kenkyū-buntansha)	平野勝也九州大学, 大学院・医学研究院, 講師 (80291516) 西村淳二九州大学, 大学院・医学研究院, 助教授 (90237727)
Keywords	ミオシン軽鎖燐酸化 / ミオシン脱燐酸化酵素 / 血管平滑筋細胞 / 細胞質Ca^<2+>濃度 / Ca^<2+>感受性 / Rho-Kinase / Y27632
Research Abstract	血管平滑筋のミオシン脱燐酸化酵素は3つのsubunit{38kDa触媒subunit、130kDa調節subunit(M130)、20kDa調節subunit(M20)}からなる。この中でM130の燐酸化は、ミオシン脱燐酸化酵素活性を阻害し、その結果、燐酸化ミオシン軽鎖の割合を増加させるため、平滑筋収縮装置のCa^<2+>感受性を増加させることが知られている。我々は、この2年間に、M130のN末端自体に血管平滑筋のCa^<2+>感受性増強作用があり、acidic clustersを含む70アミノ酸がこの作用に重要であること、またM20もCa^<2+>感受性増強作用があることを証明してきた。これまでに、Rho-kinase、ZIP like kinase、Myotonic dystrophy protein kinaseがM130の燐酸化に関与することが知られているが、その生理学的意義については不明である。本年度は家兎脳底動脈のCa^<2+>感受性制御に関与する新しいprotein kinaseの探索を試みた。αトキシンで脱膜処理を施した家兎脳底動脈中膜標本を無Ca^<2+>・無ATP・1mM ATPγSで5分間処理し、平滑筋蛋白質の不可逆性燐酸化を行った。次いで1mM ATP・Ca^<2+>添加によって収縮を引き起こさせたところ、収縮力変化量はATP・Ca^<2+>量変化から期待される変化量よりも大きいことから、ATPγS前処理は収縮装置のCa^<2+>感受性を増強させていることが明らかとなった。このCa^<2+>感受性増強作用に対して、Y27632(Rho-kinase阻害薬)はATPγS処理前に投与すると部分阻害を示したが、ATPγS処理後の投与では全く阻害効果が無かった。このRho-kinase阻害剤無効の、Ca^<2+>非依存性・ミオシン軽鎖燐酸化/Ca^<2+>感受性増強作用を示すprotein kinaseはこれまでに報告のない新しい酵素であることがわかった。現在、このprotein kinaseの単離同定を試みている。

Research Products

(11 results)

All Other

All Publications (11 results)

[Publications] Hirano K: "Cloning and functional expression of a degradation-resistant novel isoform of p27^<Kip1>"Biochem J. 353. 51-57 (2001)
[Publications] Setoguchi H: "Leukotriene C_4 enhances the contraction of porcine tracheal smooth muscle through the activation of Y-27632, a rho kinase inhibitor, sensitive pathway"Br J Pharmacol. 132. 111-118 (2001)
[Publications] Ihara E: "Ca^<2+> influx in the endothelial cells is required for the bradykinin-induced endothelium-dependent contraction in the porcine interlobar renal artery"J Physiol. 534. 701-711 (2001)
[Publications] Arimura T: "Identification, characterization and functional analysis of heart-specific myosin light chain phosphatase small subunit"J Biol Chem. 276. 6073-6082 (2001)
[Publications] Nakamura K: "Hydroxyfasudil, an active metabolite of fasudil hydrochloride, relaxes the rabbit basilar artery by disinhibition of myosin light chain phosphatase"J Cereb Blood Flow Metab. 21. 876-885 (2001)
[Publications] Shintani Y: "Mechanism of trypsin-induced contraction in the rat myometrium : The possible involvement of a novel member of protease-activated receptor"Br J Pharmacol. 133. 1276-1285 (2001)
[Publications] Ieiri S: "The mechanism for the contraction induced by Leukotrien C4 in guinea-pig taenea coli"Br J Pharmacol. 133. 529-538 (2001)
[Publications] Ohnishi Y: "Inhibitory effect of brefeldin A on the bradykinin-induced relaxation mediated by endothelium-dependent hyperpolarization in the porcine coronary artery"Br J Pharmacol. 134. 168-178 (2001)
[Publications] Nakayama T: "Mechanism of trypsin-induced endothelium-dependent vasorelaxation in the porcine coronary artery"Br J Pharmacol. 134. 815-826 (2001)
[Publications] Hirano M: "Transcriptional up-regulation of p27Kip1 during the contact-induced growth arrest in the vascular endothelial cells"Exp Cell Res. 271. 356-367 (2001)
[Publications] Ichiki T: "Downregulation of angiotensin II type 1 receptor by hydrophobic 3-hydroxy-3-mythylglutaryl coenzyme A reductase inhibitors in vascular smooth muscle cells"Arterioscler Thromb Vase Biol. 21. 1896-1901 (2001)

2001 Fiscal Year Annual Research Report

血管攣縮の分子機構:平滑筋Ca感受性亢進に関与する細胞内情報伝達網の解明

Principal Investigator

金出 英夫 九州大学, 大学院・医学研究院, 教授 (80038851)

Research Products

[Publications] Hirano K: "Cloning and functional expression of a degradation-resistant novel isoform of p27^<Kip1>"Biochem J. 353. 51-57 (2001)

[Publications] Setoguchi H: "Leukotriene C_4 enhances the contraction of porcine tracheal smooth muscle through the activation of Y-27632, a rho kinase inhibitor, sensitive pathway"Br J Pharmacol. 132. 111-118 (2001)

[Publications] Ihara E: "Ca^<2+> influx in the endothelial cells is required for the bradykinin-induced endothelium-dependent contraction in the porcine interlobar renal artery"J Physiol. 534. 701-711 (2001)

[Publications] Arimura T: "Identification, characterization and functional analysis of heart-specific myosin light chain phosphatase small subunit"J Biol Chem. 276. 6073-6082 (2001)

[Publications] Nakamura K: "Hydroxyfasudil, an active metabolite of fasudil hydrochloride, relaxes the rabbit basilar artery by disinhibition of myosin light chain phosphatase"J Cereb Blood Flow Metab. 21. 876-885 (2001)

[Publications] Shintani Y: "Mechanism of trypsin-induced contraction in the rat myometrium : The possible involvement of a novel member of protease-activated receptor"Br J Pharmacol. 133. 1276-1285 (2001)

[Publications] Ieiri S: "The mechanism for the contraction induced by Leukotrien C4 in guinea-pig taenea coli"Br J Pharmacol. 133. 529-538 (2001)

[Publications] Ohnishi Y: "Inhibitory effect of brefeldin A on the bradykinin-induced relaxation mediated by endothelium-dependent hyperpolarization in the porcine coronary artery"Br J Pharmacol. 134. 168-178 (2001)

[Publications] Nakayama T: "Mechanism of trypsin-induced endothelium-dependent vasorelaxation in the porcine coronary artery"Br J Pharmacol. 134. 815-826 (2001)

[Publications] Hirano M: "Transcriptional up-regulation of p27Kip1 during the contact-induced growth arrest in the vascular endothelial cells"Exp Cell Res. 271. 356-367 (2001)

[Publications] Ichiki T: "Downregulation of angiotensin II type 1 receptor by hydrophobic 3-hydroxy-3-mythylglutaryl coenzyme A reductase inhibitors in vascular smooth muscle cells"Arterioscler Thromb Vase Biol. 21. 1896-1901 (2001)

金出英夫九州大学, 大学院・医学研究院, 教授 (80038851)