氧化苦参碱对豚鼠心室肌细胞膜钠通道的影响

目的：研究氧化苦参碱(Oxy)对豚鼠心室肌细胞膜钠通道电流的影响，探讨Oxy在离子通道水平的作用机制。 方法: 用急性酶解法分离豚鼠心室肌细胞，应用膜片钳全细胞记录技术，观察不同浓度的Oxy对钠通道的影响。 结果: 用Oxy 1、10、100、1 000 μmol/L可浓度依赖性地抑制钠电流。在100 μmol/L时，给药后电流密度抑制约40％（P<0.01），可使心肌细胞钠电流－电压曲线上移，但激活电位、峰电位及反转电位无改变；Oxy使失活曲线向负电位方向变化，并使灭活后恢复过程延迟；对激活曲线无明显影响。 结论: Oxy可通过浓度依赖性和电压依赖性地抑制心肌细胞膜钠通道电流。

Effect of oxymatrine on sodium channel in isolated ventricular myocytes in guinea pig

AIM: To observe the effect of oxymatrine on sodium channel in isolated cardiomyocytes of guinea pig. METHODS: Single ventricular myocytes of guinea pigs were obtained by enzymatic dissociation. The whole-cell patch clamp recording technique was used to record the change of sodium current by different dosage of oxymatrine from 1 to 1 000 μmol·L-1. RESULTS: Oxymatrine decreased sodium current in a dose-dependent manner. Oxymatrine (100 μmol·L-1) decreased the current density by 40% (P<0.01). The current-voltage curve was moved up and active potential, peak potential and reverse potential had no change. The inactivation curve was moved to more negative potential and the recovery curve was delayed. The activation curve had no significant change. CONCLUSION: Oxymatrine decreases the sodium channel current in a dose-dependent and voltage-dependent manner.