牛磺酸对低氧条件下豚鼠心室肌细胞动作电位和ATP敏感性钾电流的影响  

Effect of taurine on action potentials and ATP-sensitive posstiaum channel activity during hypoxia in ventricular muscle of guinea pig

作　　者：祝芬[1] 马季骅[1] 张培华[1] 

机构地区：[1]武汉科技大学医学院,湖北武汉430080

出　　处：《中国病理生理杂志》2005年第1期92-95,共4页Chinese Journal of Pathophysiology

摘　　要：目的研究牛磺酸对低氧条件下单个豚鼠心室肌细胞膜上ATP敏感性钾电流(IK-ATP)的影响。方法应用100%纯氮饱和灌流液建立低氧模型和膜片钳全细胞记录技术。结果与对照组比较,低氧组心肌动作电位时程(APD)明显缩短,同时诱导出IK-ATP;给予牛磺酸后,使低氧时缩短的APD恢复至正常,并能剂量依赖性地抑制IK-ATP。结论牛磺酸具有抑制豚鼠心室肌细胞膜上ATP敏感钾通道(KATP)开放的作用。AIM: To study the effects of taurine on ATP sensitive potassium channel (IK_^-ATP ) during hypoxia in single ventricular myocyte. METHODS: The model of myocardial hypoxia was induced by unmixed and saturated nitrogen. IK_^-ATP activities were measured by whole-cell patch clamp recording. RESULTS: Activities of IK_^-ATP in the cell membrane of hypoxia ventricular myocyte significantly increased, compared to that in the normal. Extracellular injection of taurine (5,10,20 mmol/L) inhibited the increase in the IK_^-ATP activity in the hypoxia myocardium in a concentration-depend manner. Injection of taurine also recovered shorten APD during hypoxia. CONCLUSIONS: Taurine produces its cardioprotective effect by inhibiting the activity of IK_^-ATP in the hypoxia cardiomycytes of guinea pig. The results suggest that the depletion of taurine during myocardial hypoxia contributes to the early activation of the K_~ATP channel. [

关 键 词：牛磺酸 缺氧 心肌 细胞 动作电位 钾通道 

分 类 号：R363[医药卫生—病理学]