胺碘酮对豚鼠心室肌慢反应动作电位及收缩的抑制作用。

Inhibition by amiodarone of slow response action potentials and contraction in guinea pig ventricular muscle.

Aomine M

Department of Medicine, Northwestern University Medical School, Chicago, IL 60611.

Gen Pharmacol. 1988;19(4):621-3. doi: 10.1016/0306-3623(88)90174-7.

Abstract

Effects of an antiarrhythmic agent, amiodarone (AM), on slow response action potentials and contraction of guinea pig ventricular muscle were examined. 2. AM (4.4 x 10(-5) M, 1.1 x 10(-4) M) significantly inhibited the maximum upstroke velocity of slow response action potentials and contraction. 3. As for action potential duration (APD), higher concentration (1.1 x 10(-4) M) of AM significantly shortened the APD, while low concentration (4.4 x 10(-5) M) had little effect on it. 4. These findings strongly suggest that AM blocks slow inward current inflow via Ca2+ channels in the ventricular muscle.

摘要

研究了抗心律失常药物胺碘酮（AM）对豚鼠心室肌慢反应动作电位和收缩的影响。2. AM（4.4×10⁻⁵ M，1.1×10⁻⁴ M）显著抑制慢反应动作电位的最大上升速度和收缩。3. 至于动作电位时程（APD），较高浓度（1.1×10⁻⁴ M）的AM显著缩短APD，而低浓度（4.4×10⁻⁵ M）对其影响不大。4. 这些发现有力地表明，AM通过心室肌中的钙通道阻断慢内向电流流入。