白藜芦醇对豚鼠离体心房肌收缩力和心率的影响

Roles of potassium channel in effects of resveratrol on isolated myocardial contractility and heart rate research in guinea pig

目的:观察白藜芦醇(resvaratrol,Res)对豚鼠离体心肌收缩力(contraction force,CF)和窦房结功能的影响。方法:测定Res对离体豚鼠心房肌CF和心率(heart rate,HR)影响的量效曲线,并研究不同类型钾通道阻断剂在Res对心脏负性变时变力作用的影响。结果:Res可减慢心率(P<0.05),减弱心肌CF(P<0.05);与Res组相比,ATP敏感性钾通道(KATP)阻断剂格列苯脲(Glibenclamide,Gli)、钙激活钾通道(KCa)阻断剂四乙胺(tetraethyl-ammonium,TEA)可部分阻断Res的作用(P<0.05),电压依赖性钾通道(KV)阻断剂4-氨基吡啶(4-aminopyridine,4-AP)、内向整流钾通道(KIR)阻断剂氯化钡(barium chloride,BaCl2)、乙酰胆碱(ACh)调节钾通道(KACh)阻断剂阿托品(Atropine)不能阻断Res的作用。结论:Res可呈剂量依赖性减慢HR、减弱CF,其作用是通过开放KATP及KCa有关,与K,K和K无关。

Objective： To study the effects of resvaratrol derivatives on spontaneous HR and CF of isolated guinea pig atrium. Method： The dose-effect curve of resvaratrol was observed. The possible mechanism of potassium channels responsible for changes of CF and HR after administering with resvaratrol was measured. Result： Resvaratrol reduced the spontaneous HR and weakened the CF in a dose-dependent manner ranging from 10^-6 to 3×10^-4mol·L^-1 （P 〈0.05）. As compared with Res group, the effects were partly blocked by Gli （P 〈0. 05） and TEA （P 〈0. 01 ）, but not blocked by 4-AP, BaCl2, Atropine. Conclusion： Resvaratrol can induce negative chronotropic action and negative inotropic action. The mechanism （s） may relate to the opening of KATP and KCa.