雄性Wiste大鼠64只,体重200～300g,氨基甲酸乙酯麻醉,迅速开胸取心脏,制备左室标本,置于恒温浴槽以37℃台氏液灌流标本,充以95％O_2+5％CO_2(pH=7.4)。用常规玻璃微电极法记录心室肌细胞(VM)与浦氏纤维(PF)动作电位。测量动作电位振幅(APA)、静息电位(RP)、0相最大除极速度(V_(max))0相复极50％和90％的时程 Sixty-four male Wiste rats weighing 200-300g were anesthetized with urethane and the hearts were rapidly thoracotomized. Left ventricular samples were prepared and placed in a thermostatic bath for perfusion at 37 ℃, filled with 95% O 2 +5% CO_2 (pH = 7.4). Ventricular myocytes (VM) and Purkinje (PF) action potentials were recorded by conventional glass microelectrode method. Measurement of action potential amplitude (APA), resting potential (RP), phase 0 maximum depolarization speed (V max) 0-phase repolarization 50% and 90%