桂枝甘草汤及其拆方含药血清对豚鼠心室肌细胞L-型钙通道的影响

Effect of Guizhi Gancao Decoction and its Disassembled Prescription in Different Serum Concentrations on L-type Calcium Channel in Guinea-Pig Ventricular Myocytes

目的探讨桂枝甘草汤及不同组分含药血清对单个豚鼠心室肌细胞L-型钙离子电流(ICa-L)及其动力学参数的影响。方法急性分离豚鼠心室肌细胞,随机分为空白组、甘草组(炙甘草30 g煎液)、桂枝组(桂枝60 g煎液)、甘草加桂枝组(炙甘草30 g单煎液+等体积桂枝60 g单煎液)、桂枝甘草汤组(炙甘草30 g+桂枝60 g合煎液),共5组。实验分为10%、15%两个浓度药物组,加药完成后细胞放于37℃,5%CO_2的孵育箱中孵育24 h后进行膜片钳实验。结果与空白组比较,10%、15%各药物组均不同程度抑制钙离子电流(P<0.05),其中10%桂枝甘草汤组抑制率最大为58.4%。15%浓度药物组使ICa-L激活、失活及恢复时间均延长(P<0.05),其中桂枝组激活时间常数、慢失活时间常数和失活后恢复时间常数变化率最大;甘草组快失活时间常数变化率最大。结论桂枝甘草汤及各组分含药血清对钙离子通道有不同程度的抑制作用,与钙离子阻滞剂的作用机制相同,这可能是桂枝甘草汤抗心律失常的作用机理。

Objective To explore the effect of Guizhi Gancao Decoction（GZGC）and different serum concentrations （10% and 15%） on native L-type Ca2＊channel current（ ICa-L） in guinea pig ventricular myocytes. Methods The myocytes were isolated from guinea pig ventricular tissues, which were randomly divided into five groups： the control group, the Gancao group（ decoction of 30 g prepared Radix glycyrrhizae ）, the Guizhi group （decoction of 60 g Ramulus cinnamomi , the Gancao and Guizhi group （single decoction of 30 g prepared Radix glycyrrhizae ＋ equal volume decoction of 60 g Ramulus cinnam- omi ）, the GZGC group （co-decoction of 30 g prepared Radix glycyrrhizae and 60 g Ramulus cinnamomi ）. Cells were divided into 10% and 15% drug concentration groups and incubated at 37 ℃ in a humidified, 5% CO2 incubator after 24 h, patch clamp test was performed. Results Compared with the control group, the drug groups （ 10%, 15% ） inhibited ICa-L density to different degrees （all P 〈 0.05）, and the highest inhibition rate of 10% concentration GZGC was 58.4%. The 15% drug group increased the time courses of activation, inactivation and recovery （all P 〈0.05）. The rate of activation, slow inactivation and recovery time constant of Guizhi group was the largest, and the rate of fast inactivation time constant of Gancao group was the largest. Conclusion There were varying degrees of inhibition of Guizhi Gancao de- coction and its disassembled prescription in different serum concentration on ICa-L, the effect might be a mechanism of antiarrhythmic action, and it was the same as calcium ion inhibitor.