モルモット胃平滑筋の細胞内機序に及ぼす低酸素の効果

• 中村 江里

  名古屋市立大学・医学研究科・細胞機能制御学

• 横井 剛

  名古屋市立大学・医学研究科・細胞機能制御学

• 鈴木 光

  名古屋市立大学・医学研究科・細胞機能制御学

書誌事項

タイトル別名

• Effects of hypoxia on intracellular mechanisms of smooth muscle cells isolated from the guinea-pig stomach

抄録

Gastric smooth muscle cells generate slow waves spontaneously, and their activities may be originated from interstitial cells of Cajal. Experiments were carried out to investigate the effects of hypoxia on the activities of smooth muscle cells isolated from the guinea-pig stomach antrum by recording intracellular membrane potentials using conventional microelectrode methods, and also by measuring intracellular Ca²⁺concentration ([Ca²⁺]i) with fura-2 fluorescence. Hypoxic condition was produced by bubbling Krebs solution with N₂-gass containing 5% CO₂. Hypoxia increased the frequency of slow waves with no significant alteration to the membrane potential, and these were associated with the increase in frequency and decreased in amplitude of Ca²⁺-transients. In the presence of 10 μM cyclopiazonic acid (CPA, an inhibitor of Ca²⁺-ATPase at internal Ca stores), the increase in frequency of slow waves in response to hypoxia was abolished. In the presence of 1 mM KCN (a blocker of oxidative phosphorylation), the frequency of slow waves was decreased, with associated reduction of the amplitude. In the presence of KCN, hypoxia again increased the frequency of slow waves. These results suggest that hypoxia-induced increase in the frequency of slow waves is associated with the elevated release of Ca²⁺ from internal CPA-sensitive stores, possibly in the pacemaker cells. As the hypoxia-induced increase in the frequency is not altered by KCN, no significant contribution of mitochondrial factor in pacemaker cells is considered. [J Physiol Sci. 2006;56 Suppl:S144]

収録刊行物

• 日本生理学会大会発表要旨集

  日本生理学会大会発表要旨集 2006 (0), 144-144, 2006

  一般社団法人　日本生理学会

キーワード

• smooth muscle
• slow wave
• hypoxia
• mitochondria
• internal Ca²⁺ store

詳細情報

• CRID: 1390001205727158144
• NII論文ID: 130005448367
• DOI: 10.14849/psjproc.2006.0_144_2
• データソース種別:
  • JaLC
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可