左旋卡尼汀对大鼠缺血心肌细胞凋亡相关蛋白表达的影响

目的观察左旋卡尼汀对大鼠缺血心肌细胞凋亡相关蛋白Bcl-2和Caspase-3表达的影响。方法将SD大鼠随机分成3组:空白对照组、缺血组和左旋卡尼汀组。缺血组及左旋卡尼汀组给予异丙肾上腺素建立心肌缺血模型,左旋卡尼汀组提前经腹腔注射左旋卡尼汀。原位末端标记(TUNEL)法测定凋亡的心肌细胞,免疫组化法测定Bcl-2及Caspase-3蛋白的表达。结果左旋卡尼汀组与缺血组相比,心肌组织Bcl-2蛋白表达率显著升高,细胞凋亡率和Caspase-3蛋白表达率显著降低。结论左旋卡尼汀在异丙肾上腺素所致的心肌缺血大鼠模型中,对缺血缺氧心肌有保护作用,其机制可能是通过调节Bcl-2和Cas-pase-3介导的细胞凋亡而实现的。

Effect of L-carnitine on Expression of Cardiomyocyte Apoptosis-related Protein in Rat Model of Myocardial Ischemia

Objective To observe the effect of L-carnitine on expressions of rat cardiomyocyte apoptosis-related proteins Bcl-2 and Caspase-3.Methods Fifty SD rats were divided into 3 groups,i.e.control,model and L-carnitine groups randomly.The rats in model group were treated with isoproterenol,and those in L-carnitine group with L-carnitine prior to isoproterenol,while those in control group with physiological saline.The apoptotic cardiomyocytes were determined by TUNEL method,and the expressions of Bcl-2 and Caspase-3 proteins by immunohistochemical method.Results Compared with those in model group,the expression rates of Bcl-2 protein in cardiac muscle tissues of rats in L-carnitine group increased significantly,while the cardiomyocyte apoptosis rate and Caspase-3 protein expression rate decreased significantly.Conclusion L-carnitine may protect the myocardium of rats with isopro-terenol-induced myocardial ischemia by a potential mechanism of modulating the cardiomyocyte apoptosis mediated by Bcl-2 and Cas-pase-3.