异丙肾上腺素对心肌细胞电活动的影响及丹参的保护作用

Effects of isoproterenol on electrical activities of myocardial cellular and protective effects of "Danshen"

本实验在大鼠右心室乳头肌细胞上,观察丹参在预防异丙肾所致心肌损伤中对心肌细胞电活动的影响。异丙肾可影响心肌细胞去极化和复极化,使APA、OS和RP降低、APD延长、Vmax下降。丹参可减弱异丙肾对心肌细胞的损伤效应,使APD缩短、Vmax和OS增大,使其被控制在接近对照组水平,特别是APD_(50)的缩短尤为明显。实验结果表明,阻滞细胞膜慢通道、减少细胞内钙负荷,可能为丹参对心肌保护作用的重要途径。

Protective effects of 'Danshen' (DS) on isoproterenol (ISP)-induced myocar-dial injury caused by the electrical activities were observed on the papillary muscle cellsof rats. ISP decreased APA, OS, RP and Vmax, but prolonged APD. DS could weakenthe electrical response of the myocardial cells induced by ISP. It shortened the APD, espe-cially had marked effect on APD_(50). It increased Vmax and OS, which approached the levelof the control group. These results showed that blocking slow channel, decreasing cellular calcium loadmight be one of the important channels of the protective effects of DS on the myocardium.