硒引起冠状动脉平滑肌的舒张和细胞膜电位的降低

RELAXATION OF CORONARY ARTERIAL SMOOTH MUSCLE AND DEPOLARIZATION OF CELL MEMBRANE POTENTIAL BY SELENIUM

硒是对机体机能有重要影响的一种必需的微量元素。本工作分别应用豚鼠冠状动脉血管条张力记录的方法及平滑肌细胞内微电极记录膜电位的方法,研究了硒对平滑肌的作用。结果表明硒能引起冠状动脉平滑肌舒张及细胞膜电位去极化,而且均为剂量依赖式。硒对KCl及ACh引发收缩产生的抑制作用表现为剂量反应曲线的右移。膜电位的细胞内记录表明硒可使KCl引起的去极化作用加强以及使ACh引起的超极化作用减弱。

Selenium (Se) is an important trace element to the human being. The effects ofselenium on contraction and cell membrane potential of coronary arterial smooth musclewere studied in guinea pig by isometric force development of strips and intracellularrecording method. It was showed that Se caused vascular smooth muscle relaxation anddepolarization of the cells in a dose dependent manner. Inhibitory effect of Se on KCl-or ACh--induced contraction could be quantitatively assessed by a rightward shift of theconcentration--response curve. Furthermore, be increased KCl--induced depolarizationand decreased ACh-induced hyperpolarization.