蛇床子素通过阻断钙通道降低蛙坐骨神经复合动作电位幅度

Osthole Attenuates Compound Action Potential Amplitude of Frog Sciatic Nerve by Inhibiting Calcium Channel

目的探讨蛇床子素对蛙坐骨神经复合动作电位的作用以及离子机制。方法通过细胞外空气间隔法诱导蛙坐骨神经复合动作电位,观察蛇床子素作用及其机制。结果蛇床子素剂量依赖降低蛙坐骨神经复合动作电位幅度。胞外0钙能够减小蛇床子素的抑制效应。广谱钙通道阻断剂氯化镉,氯化镧阻断蛇床子素的抑制效应。L型钙通道阻断剂地尔硫卓、维拉帕米,P/T型钙通道阻断剂氯化镍都能阻断蛇床子素的抑制效应。结论蛇床子素通过抑制钙通道降低蛙的坐骨神经复合动作电位幅度。

Objective To investigate the effect of osthole on compound action potential amplitude of frog sciatic nerve fibers and its ionic mechanism.Methods The compound action potential of frog sciatic nerve fibers was studied by extracellular air-gap method.Results The compound action potential amplitude of frog sciatic nerve fibers was decreased in a dose-dependent manner by pretreated osthole.However,the inhibition effect of osthole on amplitude was deceasing in Ca 2+-free medium.Ca 2+channel blockers CdCl 2 or LaCl 3 blocked the inhibition effect of osthole on amplitude.L-type calcium channel blockers diltiazem,verapamil and P/T type calcium channel blockers NiCl can all block the inhibitory effect of osthole.Conclusion Osthole reduces the amplitude of the sciatic nerve complex action potential in frogs by inhibiting calcium channels.