冈田酸对培养的大鼠三叉神经元电压门控性钾和钙通道的调节(英文)  

Effects of okadaic acid on voltage-gated potassium and calcium channels in cultured rat trigeminal neurons

作　　者：谢红[1] 曹雪红[1] 明章银[1] 曹雪松[2] 雷刚[3] 李芬[3] 刘长金[3] 刘烈炬[3] 

机构地区：[1]华中科技大学同济医学院药理学系 [2]安庆市立医院,安徽安庆246003 [3]华中科技大学同济医学院生理学系,湖北武汉430030

出　　处：《中国药理学与毒理学杂志》2007年第5期369-376,共8页Chinese Journal of Pharmacology and Toxicology

基　　金：国家自然科学基金资助项目(30271500);国家自然科学基金资助项目(04510002)~~

摘　　要：目的通过研究冈田酸对大鼠三叉神经元电压门控性钾、钙电流的影响,探讨磷酸酯酶在细胞信号转导中的调节作用。方法采用全细胞膜片钳方法。结果冈田酸1μmol.L-1对瞬时外向钾电流(IA)的抑制率为28.6%,对延迟整流钾电流(IK)和钙电流(ICa)的增加率分别为22.7%和20.0%。冈田酸1μmol.L-1使IA和IK的激活曲线以及IA的失活曲线发生超级化位移,对ICa激活和失活曲线的影响没有统计学意义。结论①蛋白丝/苏氨酸磷酸酯酶1和2A可能参与了大鼠三叉神经节神经元电压门控性钾和钙通道的调节。②电压门控性钾和钙通道对蛋白丝/苏氨酸磷酸酯酶1和2A的去磷酸化反应表现出不同的依赖性。AIM To investigate the effects of serine/ threonine protein phosphatases in regulation of cell signal transduction on voltage-gated potassium and calcium channels in cultured rat trigeminal ganglion （TRG） neurons. METHODS Whole-cell patch clamp technique was used to record the potassium and calcium currents from adult rat TRG neurons before and after perfusion of okadaic acid, a potent inhibitor of the serine/threonine protein phosphatases 1 and 2A. RESULTS Okadaic acid 1 μmol·L^-1inhibited transient outwards potassium currents （IA ） by 28. 6%, increased delay rectified potassium currents （IK ） and calcium currents （Ic,） by 22.7% and 20.0%, respectively, okadaic acid 1 μmol·L^-1produced significant hyperpolarizing shifts in the conductance-voltage （G-V） curves and inactivation curves of IA, also produced significant hyperpolarizing shifts in the G-V curves of IK, while it had no effect on the activation and inactivation kinetics of Ic,. CONCLUSION Serine/threonine protein phosphatases 1 and 2A may be involved in the modulation of voltage-gated potassium and calcium channels on rat TRG neurons. In addition, voltage-gated potassium and calcium channels show different dependence on the dephosphorylation reactions of PP1 and PP2A phosphatases.

关 键 词：冈田酸 磷蛋白磷酸酶 膜片钳技术 三叉神经 神经元 离子通道 

分 类 号：R96[医药卫生—药理学]