庚醇对大鼠右心室乳头肌动作电位的影响

Effect of heptanol on action potential of papillary muscle in the right ventricle of rat

目的 探讨庚醇 (Heptanol)对大鼠缺血心肌的保护是否与其对心肌细胞动作电位的影响有关。 方法 采用常规微电极技术记录大鼠右心室乳头肌心肌细胞动作电位 ,分析参数为 :静息电位 (RP)、动作电位幅度 (APA)、有效不应期 (ERP)、动作电位的时程 (APD90 )、动作电位 0期最大除极速率 (Vmax)及动作电位传导速度 (θ) ,应用PCLab生物信号采集处理系统采集、分析。 结果 (1)不同浓度的Hep tanol对大鼠右心室乳头肌动作电位参数RP、APA、Vmax、APD90及ERP无显著影响 (P >0 .0 5 ) ;(2 )Heptanol对大鼠右心室乳头肌动作电位的传导速度有负性影响 (P <0 .0 1) ,并呈剂量依从性关系。 结论 Heptanol对缺血心肌的心肌保护作用是通过降低缝隙连结的电耦联和代谢耦联起作用的 。

Objective To investigate the protective effect of heptanol in the protection of ischemic myocardium is or not associated with the changes of the action potentials of myocardium. Methods The action potentials of papillary muscle in the right ventricle of rat were recorded by conventional glass microelectrode technique. Six parameters were measured, including resting potential (RP), action potential amplitude (APA), maximal upstroke of depolarization (Vmax),action potential duration at 90% repolarization (APD 90 ), effective refractory period (ERP)and action potential conduction velocity (θ). The signals were recorded and analyzed with microcomputer PCLab system. Results (1)Heptanol did not alter the action potential parameters and effective refractory period of papillary muscle in the right ventricle of rat(P>0.05);(2)It reduced conduction velocity of action potential of the papillary muscle in dose-dependent manner(P<0.01). Conclusion The protective effect of heptanol in the protection of ischemic myocardium is associated with decrement of gap junction intercellular communication, and is not associated with the changes of the action potentials of myocardium.