单磷酰脂A和缺血预处理对大鼠缺血/再灌注心肌细胞凋亡 Bcl-2 Bax蛋白表达的影响

目的 研究单磷酰脂A预处理(MLA-P)和缺血预处理(IP)对大鼠缺血/再灌注(I/R)心肌细胞凋亡及相关基因 Bcl-2和Bax蛋白表达的影响。方法 复制I/R损伤模型,采用末端标记技术(TUNEL)检测心肌细胞凋亡;应用免疫组化SABC法检测Bcl-2和Bax蛋白表达。结果I/R组凋亡细胞较多,MLA-P组及IP组凋亡细胞明显少于I/R组(P<0.01)。Bcl-2和Bax蛋白表达在I/R组均较多,MLA-P组及IP组Bcl-2表达明显高于I/R组(P<0.01),而Bax蛋白表达明显低于I/R组(P<0.01)。MLA-P组与IP组各指标均无显著性差异(P>0.05)。结论 MLA-P可抑制I/R诱发的心肌细胞凋亡,Bcl-2和Bax蛋白表达在心肌凋亡的发生中起重要作用。MLA-P与IP两者对心肌细胞凋亡及相关基因表达影响的作用相近。

Effects of monephosphoryl lipid A preconditioning and ischemic preconditioning on apoptosis and Bcl-2, Bax expression of myocardial cells in myocardial ischemic reperfusion in rats

Objective To study the effects of monephophoryl lipid A preconditioning(MLA - P)and ischemic preconditioning(IP)on apoptosis and Bcl - 2, Bax expression of myocardial cells in myocardial ischemic reperfusion(I/R) in rats. Methods An ischemic - reperfusion models of rats was used to conduct MLA preconditioning. Apoptotic myocyte were detected with TUNEL;Bcl- 2,Bax expression were detected with immunohistochemistry.Results The rate of apoptosis cell in I/R group were higher, the rate of apoptosis cell in MLA - P group and IP were lower significantly than those in I/R grouproup(P<0.01) .The expression of Bcl-2, Bax in I/R group was higher,the expression of Bcl-2 in MLA- P group was higher significantly than that in I/R group(P< 0.01), the expression of Bax in MLA-p group was lower than that in I/R group( P < 0.01) .There were no significant difference in MLA - P and IP group in each parameter(P > 0.05).Conclusion MLA can reduce myocyte apoptosis by I/R in rats;The expression of Bcl - 2, Bax genes have an important role in myocardial apoptosis.