甘松挥发油对大鼠心室肌细胞瞬时外向钾电流的影响论文.docVIP

　　甘松挥发油对大鼠心室肌细胞瞬时外向钾电流的影响论文 胡朗吉，葛郁芝，罗骏，杨涛，张淑华，吴志婷 【摘要】 目的研究甘松挥发油对大鼠心室肌细胞膜瞬时外向钾电流(Transient out current，Ito)的影响，探讨甘松挥发油抗心律失常作用的离子机制。 方法用急性酶解分离法获得单个大鼠心室肌细胞.freelV时，3 μg/g，6 μg/g，10 μg/g和20μg/g甘松挥发油分别抑制Ito峰值电流的抑制率为 (27.01±6.93)%(n=5)， (51.13±9.82)%(n=5)， (80.86±4.63)%(n=5)和(94.81±4.30)%(n=5)。甘松挥发油对Ito的电流密度-电压关系曲线(current density-voltage curve，I-V曲线)的影响：在+70 mV时，6μg/g甘松挥发油使Ito峰电流从(23.081±0.74)pA/pF减少到(11.232±1.47) pA/pF (n=5， P 0.05)，给药后电流密度减少约50%，给药前后电流密度变化有统计学意义。甘松挥发油对Ito激活和失活曲线的影响：在甘松挥发油6 μg/g灌流法给药后，激活曲线显示给药前后半数激活电压(V1/2)为：(36.063 ±1.792)mV vs (34.788±3.029)mV(P 0.05，n=5)；斜率因子(S) 为：(22.972±1.491)mV vs (30.791±2.899)mV(P 0.05，n=5)。给药前后半数激活电压变化无显著差异。失活曲线显示甘松挥发油使失活曲线明显左移，差异有显著统计学意义：给药前后半数失活电压(V1/2)为(-33.738±0.476)mV vs (-40.536±0.696)mV (n=5, P 0.01)；斜率因子(S)为：(5.001±0.396) mV vs (8.420±0.620) mV (n=5, P 0.01) 。结论甘松挥发油可呈浓度和电压依赖性抑制大鼠心室肌细胞Ito，使I-V曲线下移，但对激活曲线无明显影响，同时，使失活曲线明显左移，使心室肌细胞复极化减慢，这可能是其抗心律失常作用的重要机制之一。 【关键词】 甘松挥发油 膜片钳技术 瞬时外向钾电流 心室肌细胞 Abstract：ObjectiveTo observe the effects of the volatile oil of Nardostachys chinensis(VONC) on transient out current in isolated ventricular myocytes in rats. MethodsSingle ventricular myocyte of rats atic dissociation．The p recording technique anner. At concentrations of 3, 6, 10 and 20 μg/g, the peak Ito current anner. The current density of Ito pacted by the concentration at 6μg/g of the volatile oil of Nardostachys chinensis. The peak current density of Ito 23.08±0.74pA/pF (n=5, P 0.01) at membrane potential of +70 mV after treatment ent V vs (34.788±3.029) mV(n=5,.freelV vs (30.791±2.899) mV(n=5, P 0.05). The inactivation curve ent V vs (-40.536±0.696)mV (n=5, P 0.01) and Slope V vs (8.420±0.620)mV (n=5, P 0.01). ConclusionThe volatile oil of Nardostachys chinensis exercutes the blocked function to Ito in dose dependent and voltage dependent manners, and its dosage alters the I-V curve, but does not alter the active curve. Key p recording technique; Transient out current; Myocardium 甘松Nardostachys chinensis又名香松，甘香松，为败酱科植物甘松