中药甘松挥发油对大鼠心室肌细胞膜L型钙通道的影响

Effects of the Volatile Oil of Nardostachys chinensis on L-Type Calcium Channel in Isolated Ventricular Myocytes in Rats

目的研究甘松挥发油对大鼠心室肌细胞膜L型钙通道的影响,探讨甘松挥发油在离子通道水平抗心律失常的作用机制。方法用急性酶解法分离大鼠心室肌细胞,采用全细胞膜片钳记录技术,观察不同浓度的甘松挥发油对L型钙通道的影响。结果浓度为3,5,10,20,50μg/g甘松挥发油可浓度依赖性地抑制L型钙电流,在浓度为10μg/g时,给药后电流密度抑制约为(45.7±3.5)%(n=5,P<0.01),可使心肌细胞L型钙电流-电压曲线上移,但激活电位、峰电位及反转电位无改变;使激活曲线向正电位方向变化,V1/2从(-5.47±0.50)mV右移至(-2.77±0.49)mV(n=5,P<0.05);使失活曲线向负电位方向变化,V1/2从(-20.82±0.48)mV左移至(-29.44±1.03)mV(n=5,P<0.05)。结论甘松挥发油可通过浓度依赖性地抑制大鼠心肌细胞膜L型钙通道电流,使I-V曲线上移;使激活曲线右移,使失活曲线左移。

Objective To observe the effects of the volatile oil of Nardostachys chinensis on L-Type Calcium channel in isolated ventricular myocytes of rats.MethodsSingle ventricular myocytes of rat were obtained by enzymatic dissociation method.The whole—cell patch clamp recording technique was used to record the change of L-Type Calcium channel current by diferent dosage of the volatile oil of Nardostachys chinensis from 3to 50ppm.ResultsThe volatile oil of Nardostachys chinensis decreased L-type calcium channel current in a dose—dependent manner.The volatile oil of Nardostachys chinensis（10μg/g）decreased the current density by 45.7%（n=5,P0.01）,the current—voltage curve was moved up and active potential,peak potential and reverse potential had no change.The activation curve was moved to more positive potential and the inactivation curve moved to more negative potential.ConclusionThe volatile oil of Nardostachys chinensis decreases the L-Type Calcium channel current in a dose—dependent manner,the current-voltage curve was shifted upward,the activation curve was shifted towards the depolarizing direction and the inactivation curve was shifted towards the hyperpolarizing direction.