促红细胞生成素抑制caspase-3蛋白表达对缺血再灌注大鼠的心脏保护作用

目的 研究促红细胞生成素(EPO)对大鼠缺血再灌注(I/R)心肌缺血及梗死面积、心肌细胞凋亡和caspase-3蛋白表达的影响.方法 采用在体大鼠心肌I/R模型,将24只健康SD大鼠按随机数字表法随机分成3组:(1) 假手术组,以6-0号丝线在冠状动脉左前降支下穿过,不予以结扎;(2) I/R组,以6-0号丝线在冠状动脉左前降支下穿过,并结扎,在结扎线中埋置松解线,45 min后,松解结扎线,实现再灌注24 h;(3) EPO组,手术过程同I/R组,在再灌注开始即刻,给大鼠腹腔内注射重组人EPO(rhEPO),5 000 U/kg.再灌注24 h后用伊文蓝和氯化四唑(TTC)进行心肌染色,测量心肌缺血范围和梗死范围;采用原位缺口末端标记(TUNEL)检测心肌细胞凋亡;采用Western印迹法检测心肌caspase-3蛋白p17亚基的表达.结果 经过45 min缺血和24 h再灌注:心肌染色显示:假手术组心肌无缺血区和梗死区;与假手术组比较,I/R组和EPO组心肌有明显缺血区和梗死区,其缺血范围和梗死范围均显著增大(P<0.01);与I/R组比较,EPO组缺血范围略为缩小,其差异没有显著性(P>0.05),但梗死范围显著缩小(P<0.01).TUNEL结果显示:与假手术组比较,I/R组和EPO组心肌细胞凋亡显著增加(P<0.01);与I/R组比较,EPO组心肌细胞凋亡显著减少(P<0.01);Western印迹法结果显示:与假手术组比较,I/R组和EPO组caspase-3蛋白p17亚基表达水平显著升高(P<0.01);与I/R组比较,EPO组caspase-3蛋白p17亚基表达水平显著下降(P<0.01).结论 EPO显著缩小I/R大鼠心肌缺血和梗死范围,减少心肌细胞凋亡,对I/R心肌具有明显的保护作用,其机制可能与下调caspase-3蛋白表达相关.

Cardio-protection of erythropoietin on the rats with ischemia-reperfusion injury through inhibiting caspase-3 protein expression

Objective To study the protective effects of erythropoietin(EPO) on the myocardium and its influence on the expression of caspase-3 protein in rats during ischemia-reperfusion(I/R) injury.Methods 24 healthy male SD rats were randomly divided into: sham-operated,I/R and EPO groups.In sham-operated group,the left anterior descending(LAD) coronary artery was exposed without further procedures.In I/R group,the LAD coronary artery was reperfused for 24 hours following 45 minutes occlusion.In EPO group,the rats w...