【摘要】 目的:研究灯盏花素对大鼠心室肌细胞膜钠通道的影响,在离子通道水平探讨灯盏花素的抗心律失常作用机制。方法:用急性酶解法获得单个大鼠心室肌细胞,标准的全细胞膜片钳技术记录钠通道电流(INa)。结果:(1)灯盏花素呈浓度依赖性抑制INa,在-30 mV时,含1、3、30、100 mg.L-1灯盏花素的细胞外液分别灌流细胞3 min,分别阻断INa峰电流(7.98±0.60)%、(37.73±2.31)%、(65.58±2.90)%和(88.09±5.60)%。INa激活电位为-70 mV,最大峰电位为-30 mV,翻转电位为5 mV,激活和失活过程呈电压和时间依赖性。30 mg.L-1灯盏花素使电流电压曲线明显上移,峰值电流从(13.49±1.25)pA/pF减少至(4.78±0.85)pA/pF,n=8,P<0.05,冲洗后可以不完全恢复。(2)灯盏花素能使钠电流失活曲线明显左移。(3)灯盏花素使钠电流激活曲线明显右移。(4)灯盏花素使钠电流复活明显减慢。结论:灯盏花素能够抑制心肌细胞钠通道电流,并呈浓度依赖性。更多还原

【Abstract】 AIM: To investigate the effects of breviscapine on INa channel in isolated rat ventricular myocytes.METHODS: Single cell of rat ventricular myocyte was isolated by enzymatic dissociation.The whole-cell patch-clamp recording technique was used to observe the change of INa channel current influenced by breviscapine.RESULTS: Breviscapine decreased the INa channel current in a dose-dependent and voltage-dependent manner in rat ventricular myocytes.The current-voltage curve was significantly decreased.Breviscapin at concentrations of 1,3,30,100 mg/L respectively decreased INa current density,which were(7.98±0.60)%,(37.73±2.31)%,(65.58%±2.90)% and(88.09±5.60)%,respectively.INa was inhibited in a voltage-dependent manner,showing a significant attenuating effect at test potentials from-30 mV to 0.The INa inactivation curve was shifted to left and the activation curve was shifted to right.Breviscapine step down the recovery curve significantly.CONCLUSION: Breviscapine concentration-dependently decreased INa channel current in rat ventricular myocytes.更多还原