雷公藤多甙对蟾蜍缝匠肌终板膜乙酰胆碱受体的作用

The Effect of TWP on the Reactivity of AChR on the End-plate Membrane of Frog Sartorius

目的 观察雷公藤多甙 (TWP)对终板膜乙酰胆碱受体 (n ACh R)的反应性的作用。方法 在不均匀牵张法制动的蟾蜍缝匠肌标本上 ,利用微电泳氯化乙酰胆碱 (ACh Cl)技术 ,在终板区引起的乙酰胆碱电位 (ACh P)来反映终板膜 n ACh R的反应性。结果 12 0 mg/ L TWP组 ,用药 2 0 m in后 ACh P振幅明显升高 ,4 0 mg/ L 和 6 0mg/ L TWP组 ,用药 10 m in后 ACh P振幅明显升高 ;2 2 0 mg/ L 和 4 0 m g/ L TWP组内 ,ACh P振幅除 80 m in组外 ,其它各时间组间有显著性差异 (P<0 .0 5 ) ,6 0 min达最大值 ;36 0 mg/ L TWP组 ,在用药后 4 0 m in、 6 0 m in和80 m in均记录到动作电位 (AP) ;4药物各浓度组引起的 ACh P振幅变化率之间有显著差异 (P<0 .0 5 ) ,其中 6 0mg/ L TWP组引起的变化率最大。结论 TWP能提高终板膜 n ACh R的反应性 。

Objective To study the effect of Tripterygium Wilfordii Polyglycosidium (TWP) on the reactivity of n Acetylcholine recepter (nAChR) on the end plate membrane. Methods Using the microionophoretic method, we applied the exogenous acetylcholine chloride (AChCl) to the superficial end plates of the isolated nonuniform stretched frog sartorius, and acetylcholine potential (AChP) recorded was taken as an indicator of the reactivity of the nAChR in the end plate. Results ① After the addition of TWP, the apparent change of AChP was recorded at 20 min in the 20 mg/L group ,and at 10 min in the 40 mg/L and 60 mg/L groups respectively. ②Within the 20 mg/L and 40 mg/L TWP groups, the change in amplitude of AChP showed significant difference with the time ( P <0.05), the greatest being at 60 min.③ In the 60 mg/L TWP group, action potential was recorded at 40 min, 60 min and 80 min.④ There was significant difference in the percentage of AChP amplitude change between the three concentration groups ( P <0.05), and the highest percentage of change appeared in the 60 mg/L group. Conclusion TWP can increase the reactivity of nAChR in the end plate membrane, and there exist an apparent concentration effect relationship and a certain time effect relationship.