目的 :研究氨氯吡咪 (AM)及其衍生物二甲基氨氯吡咪 (DMA)对心室肌细胞跨膜动作电位时程(APD)的影响。方法 :利用全细胞膜片钳技术 ,观察 AM及其衍生物 DMA对豚鼠心肌细胞跨膜 APD的作用。结果 :Am可使 APD复极化 3 0 %、5 0 %和 90 %的时程 (APD3 0 ,APD50 ,APD90 )延长 3 0 %、5 2 %和 3 4%。 DMA可使APD复极化 APD3 0 、APD50 、APD90 的时程缩短 4 0 %、2 9%和 2 4 %。结论 :AM可使心肌细胞跨膜 APD延长 ,而DMA可使心肌细胞跨膜 APD缩短 AIM: To investigate the effect of amiloride (AM) and its derivative dimethylamino-clopidogrel (DMA) on the transmembrane action potential (APD) of ventricular myocytes. Methods: The whole cell patch clamp technique was used to observe the effect of AM and its derivative DMA on transmembrane APD in guinea pig ventricular myocytes. RESULTS: Am prolonged 30%, 52% and 34% of APD repolarised 30%, 50% and 90% of the time course (APD30, APD50, APD90). DMA can shorten the time course of APD repolarization APD30, APD50 and APD90 by 40%, 29% and 24%. Conclusion: AM can prolong the transmembrane APD of myocardial cells, while DMA can shorten the transmembrane APD of myocardial cells