促红细胞生成素预处理在心肌缺氧复氧损伤中对凋亡相关基因表达影响的研究  

Effect of erythropoietin pretreatment on the expression of apoptosis-associated genes in hearts of rats during hypoxia-reoxygenation injury

作　　者：秦川[1] 肖颖彬[1] 陈林[1] 钟前进[1] 王学锋[1] 

机构地区：[1]第三军医大学附属新桥医院心血管外科,重庆400037

出　　处：《心肺血管病杂志》2008年第2期109-112,共4页Journal of Cardiovascular and Pulmonary Diseases

摘　　要：目的:观察促红细胞生成素(erythropoietin,EPO)预处理在大鼠心肌缺氧复氧损伤(hypoxia/reoxygenation,H/R)中的抗凋亡效应以及对凋亡相关基因bcl-2及bax表达的影响。方法:Wistar成年雄性大鼠60只,分为2组,分别为对照组,EPO预处理组(EPO组),每组30只,EPO组大鼠经腹腔注射5000U/kg重组人促红细胞生成素(Recombinant human erythropoietin,RHuEPO),对照组注射同体积生理盐水。2组各15只大鼠于给药24h后,检测各项指标,其余15只大鼠置于常压缺氧环境中(O27%)12h后,移至常压常氧环境中2h,予H/R损伤,之后采取心肌标本,DNA末端转移酶标记法(TUNEL法)检测心肌细胞凋亡,免疫组化检测凋亡效应酶胱天蛋白酶-3(caspase-3)、凋亡相关基因B细胞淋巴瘤/白血病-2(B-cell lymphoma/leukemia-2,bcl-2)及B细胞淋巴瘤/白血病相关x蛋白(Bcl-associated x protein,bax)蛋白表达水平,计算bcl-2/bax比值。结果:H/R损伤前2组心肌细胞凋亡率,caspase-3以及bax蛋白表达水平无显著性差异(P>0.05),EPO组bcl-2蛋白表达水平、bcl-2/bax比值显著高于对照组(P<0.01)。H/R损伤后2组心肌细胞凋亡率,caspase-3、bax及bcl-2蛋白表达水平显著高于损伤前(P<0.01),而bcl-2/bax比值显著低于损伤前(P<0.01),EPO组的心肌细胞凋亡率、caspase-3蛋白表达水平显著低于对照组(P<0.05,P<0.01),而bcl-2蛋白表达水平以及bcl-2/bax比值显著高于对照组(P<0.05,P<0.01),2组bax蛋白表达水平差异无显著性(P>0.05)。结论:EPO预处理在心肌H/R损伤中具有显著的抗凋亡效应;这一效应与其上调抗凋亡基因bcl-2的表达有关。Objective：This study is to observe the effect of EPO pretreatment on the expression of bcl-2 and bax in myocardium of rats during H/R injury. Method：60 male adult Wistar rats were randomly divided into 2 groups： control group and EPO pretreatment group （EPO group）. The rats in EPO group received peritoneal injection of 5000 U/kg RHuEPO, and control group received the peritoneal injection of the same volume of saline. 24 hours after the pretreatment, 15 rats in each group were examined for all the designed indexes in this study. The other 15 rats in each group were exposed to hypoxia （O2 7%）for 12 hours and then exposed to normoxia for 2 hours （reoxygenation）. Myocardium was harvested in all of rats. Apoptosis and the expression of bcl-2 and bax was detected. Bcl-2/bax ratio was calculated. Result：There was no significant difference in apoptosis and the expression of bax between the 2 groups before H/R（P〉0.05）. The expression of bcl-2 and bcl-2/bax ratio were higher in EPO group than in control group before H/R（P〈0.01）. After H/R, apoptosis and the expression of bcl-2 and bax in both groups increased significantly compared to what before H/R（P〈0.01）. However, bcl-2/bax ratio in both groups significantly decreased compared to what before H/R（P〈0.01）. Apoptosis level was lower in EPO group than that in control group after H/R（P〈0.05,P〈0.01）. The expression of bcl-2 and bcl-2/bax ratio were higher in EPO group than that in control group after H/R（P〈0.05,P〈0.01）. There was no marked difference in the expression of bax between 2 groups after H/R（P〉0.05）. Conclusion：EPO pretreatment can inhibit the apoptosis in myocardium of rats insulted with H/R injury and this effect may be related to the upregulation of bcl-2 gene and the elevation of bcl-2/bax ratio induced by EPO pretreatment.

关 键 词：促红细胞生成素 心肌 B细胞淋巴瘤/白血病-2 B细胞淋巴瘤/白血病相关x蛋白 

分 类 号：R392.12[医药卫生—免疫学]