Hatem S, Le Grand B, Le Heuzey J Y, Couétil J P, Deroubaix E
U 256 INSERM, Instrumentation et dynamique cardiovasculaire, Hôpital Broussais, Paris, France.
Basic Res Cardiol. 1992 Nov-Dec;87(6):600-9. doi: 10.1007/BF00788670.
Quinidine and flecainide, two class-I antiarrhythmics increase action potential duration (APD) at 90% repolarization and cellular refractory period in human atrial fibers without significant change in resting potential. On the other hand, quinidine decreases APD at 50%, whereas flecainide slightly increases, which suggests different effects on Ca2+ current. Using isolation cell procedure and whole cell recording, we found that 10 microM quinidine (34.77 +/- 6.5%, n = 5) and 0.5 microM flecainide (50.46 +/- 6.2%, n = 4) decrease calcium current in human atrium. It is concluded that, at therapeutical concentrations, quinidine and flecainide modify the action potential plateau phase in a different manner, which is not only related to the calcium current decrease.
奎尼丁和氟卡尼这两种I类抗心律失常药可增加人类心房纤维在90%复极化时的动作电位时程（APD）和细胞不应期，而静息电位无显著变化。另一方面，奎尼丁可降低50%的APD，而氟卡尼则略有增加，这表明它们对钙电流有不同影响。采用细胞分离技术和全细胞记录方法，我们发现10微摩尔/升的奎尼丁（34.77±6.5%，n = 5）和0.5微摩尔/升的氟卡尼（50.46±6.2%，n = 4）可降低人类心房的钙电流。得出的结论是，在治疗浓度下，奎尼丁和氟卡尼以不同方式改变动作电位平台期，这不仅与钙电流降低有关。
