An R H, He R R
Department of Physiology, Hebei Medical College, Shijiazhuang, China.
Zhongguo Yao Li Xue Bao. 1991 Jan;12(1):36-9.
The effects of m-nisoldipine (m-Nis) and nisoldipine (Nis) on the electrical activity of pacemaker cells in sinoatrial node (SAN) of rabbit were studied using intracellular microelectrodes.
APA and Vmax in SAN pacemaker cells were markedly reduced by m-Nis and Nis. The inhibitory effects of Nis on APA and Vmax were greater than those of the m-Nis. Elevation of Ca2+ concentration in the perfusate partially antagonized the inhibitory actions of m-Nis and Nis. VDD of SAN pacemaker cells were reduced by m-Nis. The change of RPF was not consistent with that of VDD. CSRT was prolonged by m-Nis and Nis in a dose-dependent manner. The inhibitory effects of Nis on SAN pacemaker cells were greater than that of the m-Nis. Both MDP and APD50 were not affected by m-Nis and Nis.
使用细胞内微电极研究了间尼索地平（m-Nis）和尼索地平（Nis）对兔窦房结（SAN）起搏细胞电活动的影响。
m-Nis和Nis显著降低了SAN起搏细胞的APA和Vmax。Nis对APA和Vmax的抑制作用大于m-Nis。灌注液中Ca2+浓度升高部分拮抗了m-Nis和Nis的抑制作用。m-Nis降低了SAN起搏细胞的VDD。RPF的变化与VDD的变化不一致。m-Nis和Nis以剂量依赖性方式延长了CSRT。Nis对SAN起搏细胞的抑制作用大于m-Nis。MDP和APD50均不受m-Nis和Nis影响。
