An R H, He R R
Department of Physiology, Hebei Medical College, Shijiazhuang, China.
Zhongguo Yao Li Xue Bao. 1990 Jul;11(4):310-4.
The effects of m-nisoldipine (m-Nis) and nisoldipine (Nis) on action potentials of papillary muscles in guinea pigs were studied using intracellular microelectrodes.
(1) APD and Vmaxs in normal papillary muscles were reduced by m-Nis and Nis. However, the APA, Vmaxf and overshoot were not affected. (2) In the partially depolarized papillary muscles, the APA, overshoot, Vmax and APD were depressed in a dose-dependent manner. The inhibitory effects of Nis on APA, APD50 and PPD were greater than those of the m-Nis. (3) There was a good correlation between APD50 and PPD derived from a linear regression. By the linear equation, PPD was easily calculated from APD50.
使用细胞内微电极研究了间尼索地平（m-Nis）和尼索地平（Nis）对豚鼠乳头肌动作电位的影响。
（1）m-Nis和Nis可降低正常乳头肌的动作电位时程（APD）和最大上升速率（Vmaxs）。然而，动作电位幅度（APA）、最大上升速率（Vmaxf）和超射值不受影响。（2）在部分去极化的乳头肌中，APA、超射值、Vmax和APD呈剂量依赖性降低。Nis对APA、50%动作电位时程（APD50）和动作电位复极90%至50%时程（PPD）的抑制作用大于m-Nis。（3）由线性回归得出的APD50和PPD之间存在良好的相关性。通过线性方程，可根据APD50轻松计算出PPD。
