缺血预适应与后适应对家兔局部短期缺血再灌注心肌细胞凋亡影响的研究

目的：探讨缺血预适应与缺血后适应对兔局部缺血再灌注，心肌细胞凋亡的影响。方法：用30只新西兰大白兔建立心肌缺血再灌注动物模型，采用DNA电泳和TUNEL分析检测缺血再灌注心肌组织的细胞凋亡情况，免疫组化方法检测心肌组织中Bcl-2和Bax蛋白的表达。结果：缺血再灌注组缺血区心肌DNA电泳出现200bp，400bp2条条带呈梯形，其余各组未见梯形；TUNEL检测显示缺血再灌注组心肌细胞凋亡指数较其他实验组显著增加（P〈0．05）；缺血再灌注组Bcl-2基因蛋白表达量低于其他各组（P〈0．05）；缺血再灌注组Bax基因蛋白表达量高于其他各组（P〈0．05）。结论：缺血后适应可产生内源性心脏保护作用。缺血预适应、缺血后适应显著减轻了兔缺血再灌注诱导的心肌细胞凋亡程度与上调Bcl-2蛋白表达、下调Bax蛋白表达有关。

Effects of ischemic preconditioning and ischemic postconditioning on myocardial cell apoptosis during the short periods of ischemia/reperfsion in rabbit

Objective： To investigate the effects of ischemic preconditioning （IP） and ischemic postconditioning （Post） on myocardial cell apoptosis and expression of Bcl -2 and Bax protein during ischemia/reperfusion period in rabbits. Methods：All studies were performed on 30 healthy New Zealand rabbits. Cardiomyocyte apoptosis was determined by in situ TUNEL and DNA electrophoresis. The expression of Bcl - 2 and Bax proteins were detected by immunohistochemiscal method. Results： DNA electrophoresis showed that there were two ladder - shaped straps of 200 bp and 400bp in the myocardium of ischemic region in the IR group;TUNEL detection showde that the apoptotic index in IP group,Post group and IP ＋ Post group were obviously lower than that in the IR GROUP（ P 〈0. 05 ） ;The expression of Bcl - 2 protein in IP group, Post group and IP ＋ Post group higher than that in the IR group（ P 〈 0.05 ） ;The expression of Bax protein in Is group,Post group and IP ＋ Post group were lower than that in the IR group （ P 〈 0.05 ） Conclusion： IP and Post has robust myocardial protection in rabbits in IRI. IP and Post significantly decreases the ration of apoptosis and protects myocardial cells from IPI by increasing Bcl -2 expression and decreasing Bax expression.