牛磺酸对心肌缺血损伤细胞凋亡与Fas/FasL基因表达变化的影响

目的探讨大鼠心肌缺血损伤心肌细胞凋亡与Fas/FasL基因表达变化及牛磺酸对其的影响。方法结扎冠状动脉制备心肌缺血模型,转移酶介导脱氧尿苷三磷酸缺口末端标记法检测心肌凋亡细胞,免疫组织化学法检测Fas/FasL蛋白水平,反转录-聚合酶链反应(RT-PCR)法分析Fas基因mRNA表达变化。结果心肌缺血后心肌细胞凋亡指数、Fas/FasL蛋白阳性染色细胞指数及Fas基因的mRNA表达水平均明显增加,心肌组织超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量升高,Ca2+-ATP酶活性降低。牛磺酸能明显降低心肌细胞凋亡指数,Fas基因mRNA表达及Fas/FasL蛋白阳性染色细胞指数,抑制心肌组织MDA的生成,提高Ca2+-ATP酶活性。结论牛磺酸对心肌缺血的心肌细胞凋亡与Fas/FasL基因表达水平增高有较好的拮抗作用。

Taurine effects on the apoptosis of ischemia-injured myocardial cells and on the expression changes of Fas/FasL genes

Objective To investigate the changes of apoptosis of ischemia-injured myocardial cells and the ex-pression of Fas/FasL genes in rat and the effects of taurine on them.Methods Rat models with myocardial ischemia were established by occluding left coronary artery(LCA).Transferase-mediated dUTP nick end labeling(TUNEL)and immuno-histochemical staining were used respectively to detect the changes of apoptosis and protein expression of Fas/FasL genes;mRNA expression of Fas gene was evaluated by RT-PCR analysis.Results Apoptosis index,positive index of Fas protein,and mRNA expression of Fas gene were all increased in the rat' s ischemic myocardium,the level of myocardial MDA,SOD increased,but Ca 2 -ATPase activity decreased.Taurine can significantly decresae apoptosis index,positive index of Fas protein,mRNA expression of Fas gene,and MDA content in the ischemic myocardium,but increase Ca 2 -ATPase activ-ity.Conclusion Taurine exerts a good antagonist action on the apoptosis of ischemia-injured myocardial cells and the increased expression of Fas/FasL expression.