Goupil N, Lenfant J
Eur J Pharmacol. 1976 Sep;39(1):23-31. doi: 10.1016/0014-2999(76)90109-6.
The action of amiodarone (1.5 X 10(-5) M) on sinus node activity of spontaneously beating isolated right atria of rabbit at 30 degrees C was investigated using a microelectrode technique. The drug significantly increased the action potential duration and decreased the slope of diastolic depolarization, both effects leading to a reduction of the sinus rate. In contrast to beta-blocking agents, amiodarone reduced but did not completely abolish the adrenergic effects on the sinus node activity. It is concluded that the amiodarone-induced bradycarida observed in clinical trials might be due to a direct effect of the drug on the sinus node.
在30摄氏度下,采用微电极技术研究了胺碘酮(1.5×10⁻⁵M)对兔离体自发搏动右心房窦房结活动的作用。该药物显著延长动作电位时程并降低舒张期去极化斜率,这两种效应均导致窦性心率降低。与β受体阻滞剂不同,胺碘酮可降低但并未完全消除肾上腺素能对窦房结活动的影响。得出的结论是,临床试验中观察到的胺碘酮所致心动过缓可能是该药物对窦房结的直接作用所致。