促红细胞生成素对心肌缺血再灌注损伤大鼠心肌的保护作用  

Protective effect of erythropoietin on myocardium of rats with ischemia-reperfusion injury

作　　者：邱炯[1] 赵玉伟[1] 李法琦[1] 周平[1] 李万玉[2] 

机构地区：[1]重庆医科大学附属第一医院老年病科心血管病组,重庆400016 [2]重庆医科大学药学院药剂学教研室,重庆400016

出　　处：《吉林大学学报（医学版）》2012年第5期912-917,I0001,共7页Journal of Jilin University：Medicine Edition

基　　金：重庆市自然科学基金资助课题(CSTC;2007BB5294)

摘　　要：目的:探讨促红细胞生成素(EPO)对心肌缺血再灌注(I/R)大鼠缺血及梗死面积的影响,阐明EPO对心肌I/R损伤的保护作用的机制。方法:采用在体大鼠心肌I/R模型,将24只健康雄性SD大鼠随机分为假手术组(n=8),以6-0号丝线在冠状动脉左前降支下穿过,不予以结扎;I/R组(n=8),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,45min后,松解结扎线,实现再灌注;EPO组(n=8),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促红细胞生成素(rhEPO),5 000U.kg-1。再灌注24h后用多导生理仪记录大鼠血流动力学指标,包括收缩压(SP)、舒张压(DP)、左室收缩压(LVSP)、左室舒张压(LVDP)、左室舒张末期压(LVEDP)、心室收缩期室内压上升最大速率(dp/dtmax)和心室舒张期室内压下降最大速率(dp/dtmin)的变化;用原位缺口末端标记法(TUNEL)检测心肌细胞凋亡;用Evan’s blue和氯化三苯基四氮唑(TTC)进行心肌染色,测量心肌缺血及梗死范围。结果:45min的缺血和24h的再灌注血流动力学检测显示,3组大鼠SP、DP和LVSP无明显差异(均P>0.05);与假手术组比较,I/R组大鼠LVDP和LVEDP明显升高,但dp/dtmax和dp/dtmin明显下降(均P<0.05);与I/R组比较,EPO组LVDP、LVEDP、dp/dtmax和dp/dtmin均有明显改善(均P<0.05)。TUNEL结果显示,与假手术组比较,I/R组和EPO组大鼠心肌细胞凋亡明显增加(均P<0.05);与I/R组比较,EPO组大鼠心肌细胞凋亡显著减少(P<0.05)。心肌染色显示,假手术组大鼠心肌无缺血区和梗死区;与假手术组比较,I/R组和EPO组大鼠心肌有明显缺血区和梗死区;与I/R组比较,EPO组大鼠缺血范围略为缩小,但差异无统计学意义(P>0.05),梗死范围明显减少(P<0.05)。结论:EPO能够显著缩小I/R大鼠的心肌缺血及梗死范围,减少心肌细胞凋亡,显著改善其血流动力学和心脏功能,进而对心肌I/R损伤起保护作用。Objective To probe the influence of erythropoietin（EPO） on ischemic size and infarction size of rats with myocardial ischemia-reperfusion（I/R） injury and to clarify the mechanism of the protective effect of EOP on myocardial I/R injury.Methods 24 healthy male SD rats were randomly divided into sham-operated group（n=8）,I/R group（n=8） and EPO group（n=8）.In sham-operated group,the 6-0 thread was passed through the left anterior descending（LAD） coronary artery of rats without further procedures;in I/R group,the LAD coronary artery were ligated and embedded slack line in the ligature line and reperfusion was performed 45 min later;in EPO group,the rats had the same surgical procedures as I/R group and were administered by intraperitoneal injection of recombinant human erythropoietin（rhEPO） 5 000 U·kg-1.The hemodynamic parameters including systolic pressue（SP）,diastolic pressure（DP）,left ventricular systolic pressure（LVSP）,left ventricular diastolic pressure（LVDP）,left ventricular end-diastolic pressure（LVEDP）,maximal rate of increase of ventricular pressure（dp/dtmax） amd maximal rate of decrease of ventricular pressure（dp/dtmin） were determined by multiple channel electrophysiolograph after 24 h reperfusion.The apoptotic index of cardiomyocytes was investigated by TdT-mediated dUTP nick end labeling（TUNEL） method.The ischemia and infarction size of hearts were measured by double staining with TTC-Evan＇s blue dye.Results After 45 min ischemia and 24 h reperfusion,there were no significant differences in SP,DP and LVSP between three groups（P0.05）.Compared with sham-operated group,LVDP and LVEDP were significantly increased while dp/dtmax and dp/dtmin were reduced remarkably in I/R group（P0.05）;compared with I/R group,LVDP and LVEDP were decreased significantly but dp/dtmax and dp/dtmin were increased remarkably in EPO group（P0.05）.The results of the myocardial TUNEL staining revealed that the TUNEL positive cardiomyocytes were increased dramatica

关 键 词：促红细胞生成素 心脏 缺血再灌注损伤 血流动力学状况 细胞凋亡 梗死面积 

分 类 号：R541.4[医药卫生—心血管疾病]