大鼠心肌IP对I/R心肌细胞凋亡及bclxl蛋白表达的影响

The Effect of Ischemic Preconditioning on Cardiac Myocyte Apoptosis and bcl-xl Expression During Myocardial Ischemia/Reperfusion Course in Rat

目的 :研究缺血预适应 (ischemicpreconditioning ,IP)对大鼠缺血再灌注 (ischemia/reperfusion ,I/R)心肌细胞凋亡和凋亡抑制基因bcl xl蛋白表达的影响。方法 :采用末端脱氧核苷酸转移酶介导的带萤光的dUTR缺口末端标记 (TUNEL)法和免疫组化方法。结果 :IP组TUNEL法阳性心肌细胞核数量及阳性心肌细胞核占总心肌细胞核数的百分比均明显少于I/R组 (P <0 .0 5或 0 .0 1) ;IP组表达bcl xl蛋白阳性的心肌细胞数及阳性心肌细胞占心肌细胞总数的百分比均明显高于I/R组 (P <0 .0 1)。结论 :大鼠心肌IP能够显著减少I/R心肌细胞凋亡 ;IP通过上调凋亡抑制基因bcl xl基因表达可能是其减少I/R心肌细胞凋亡的机制之一。

Objective:To explore the protective effect of ischemic preconditioning(IP) on cardiac myocyte apoptosis and bcl xl expression during myocardial ischemia/reperfusion(I/R) course in rats. Methods:TUNEL and immunohistochemichal methods were used. Results:The numbers of positive cardiac myocyte nuclear and its percentage in IP group decreased significantly(P<0.05 or 0.01) compared with that of I/R group The numbers of protein bcl xl positive cardiomyocyte and its percentage in IP group were bigger(P<0.01) than that of I/R group. Conclusion:The protection of IP could decrease cardiomyocyte apoptosis . Up regulating expression of protein bcl xl in cardiomyocytes during I/R course might be one of the protection mechanisms of ischemic preconditioning.