腺苷对不同部位心肌细胞的电生理作用比较

COMPARISON OF THE ELECTROPHYSIOLOGIC EFFECTS OF ADENOSINE ON ATRIAL, VENTRICULAR AND ATRIOVENTRICULAR MYOCARDIUM FROM GUINEA PIG HEART

运用标准玻璃微电极技术记录豚鼠心房肌、心室肌及房室结区细胞动作电位．比较和研究腺苷对它们的电生理作用。结果表明．腺苷可明显缩短心房肌细胞AP房室结区细胞的APD．并降低房室结区细胞APA及Vmax．而对心室肌细胞AP各参数无影响。其作用可被选择性A1受体拮抗剂DPCPX所消除．本文同时还探讨了踪着对不同部位心肌细胞产生不同效应的可能机制。

Using microelectrde technique recording action potential, We compared the effects ofadenosine on atrial, ventricular and atrioventricular myocytes. The results indicated: To atrial myocytes,Ado cou1d shorten APD but had no effects on RP, APA and Vmax. To atrioventricular cells, Adenosine couldreduce APA and Vmax, shorten APD. To ventricular myocytes, Ado hadn't any obvious actions. These actions of Ado could be antagonized by DPCPX. This artlcle also discussed the mechanism that adenosine haddifferent action to atrial. ventricular and atrioventricular myocardium.