葛根素对大鼠心室肌细胞钠通道的影响

Effects of puerarin on sodium channel current in isolated ventricular myocytes of rats

目的研究葛根素对大鼠心室肌细胞膜钠通道电流的影响,探讨葛根素在离子通道水平的作用机制。方法用急性酶解法获得单个大鼠心肌细胞,用标准全细胞膜片钳技术记录钠通道电流。结果0.3,1,3g/L葛根素能剂量依赖性增加钠通道电流,增加值分别(3.4±0.5)%、(34.1±2.7)%和(55.9±2.5)%,n=5。1g/L葛根素能使心肌细胞钠通道电流鄄电压曲线显著下移,最大峰电流密度从(17.4±1.6)pA/pF增加至(23.3±1.8)pA/pF,n=5,P<0.05,但原有的电流鄄电压依赖特征不变;葛根素对钠通道电流失活和复活曲线也无明显影响。1μmol/L普萘洛尔能明显阻断1g/L葛根素增加钠通道电流作用。结论葛根素能浓度依赖性地增加心肌钠大鼠通道电流。

Objectives To determine the effects of puerarin on sodium channel current in isolated ventricular myocytes of rats; To explore the mechanism of puerarin at the ionic channel level. Methods Single ventricular myocytes of rats were isolated by enzymatic dissociation. The whole-cell pacth clamp recording technique was used to record the change of sodium channel current influenced by puerarin. Results Puerarin increased the sodium channel current in a dose-dependent and voltage-dependent manner in ventricular myocytes of rats. 1. The current-voltage curve was shifted downwards, which active potential, peak potential and reverse potential had no significant changes. 2. The activation, inactivation and recovery curves were not altered. 3. Propranolol blocked the effect of puerarin. Conclusions Puerarin concentration-dependently increased sodium channel current in ventricular myocytes of rats.