心肌肽素抑制大鼠心室肌细胞瞬时外向钾电流  

Cardiomyopeptidin decrease transient outward potassium current of rat ventricular myocytes

作　　者：吴辉[1] 李立环[1] 陈雷[1] 黄爱杰[1] 

机构地区：[1]中国医学科学院中国协和医科大学阜外心血管病医院麻醉科

出　　处：《基础医学与临床》2006年第10期1118-1121,共4页Basic and Clinical Medicine

摘　　要：目的研究新药心肌肽素对大鼠心室肌细胞瞬时外向钾电流(Ito)的影响及其在离子通道水平的作用机制。方法用急性酶解法分离大鼠心室肌细胞,用标准的全细胞膜片钳技术,观察不同浓度的心肌肽素对Ito的影响。结果心肌肽素呈浓度依赖性抑制大鼠心室肌细胞Ito,心肌肽素浓度(mg/L)为10、50、100、250和500时分别使Ito降低(%)4、13、22、32和38。心肌肽素50 mg/L使Ito电流密度-电压曲线下移,但不改变曲线的形状,也不改变Ito稳态激活曲线。结论心肌肽素抑制大鼠心室肌细胞Ito,可能是其抗心律失常作用的机制之一。Objective To determine the effect of cardiomyopeptidin on transient outward potassium current （ Ito ） of rat ventricular myocytes and its action mechanism on the ion channels of myocardium. Methods Single ventricular myocytes of rats were obtained by enzymatic dissociation. The whole-cell patch-clamp recording technique was used to record the change of transient outward potassium current （Ito） by different dosages of cardiomyopoptidin. Results Cardiomyopoptidin decreased Ito in a dose-dependent manner. Cardiomyopoptidin in dose of 10, 50, 100,250 and 500 mg/L decreased Ito （ % ） by 4, 13, 22, 32 and 38 respectively. Cardiomyopeptidin 50 mg/L moved the current density-voltage curve of Ito down, but the shape of the curve had no changes. Cardiomyopeptidin 50 mg/L did not change the steady state activation curve of Ito. Conclusions Cardiomyopoptidin decreases the Ito of rat ventricular myocytes, which might be one of the mechanisms of its antiarrhythmic effect.

关 键 词：肽类 心肌细胞 电压门控性钾通道 膜片钳技术 

分 类 号：R96[医药卫生—药理学]