双下肢缺血预处理对未成熟心肌细胞凋亡和相关凋亡蛋白表达的影响

目的　探讨双下肢缺血预处理对未成熟心肌细胞凋亡和 B淋巴细胞瘤 /白血病 2蛋白 (bcl- 2 )、bcl- 2家族 bax蛋白、神经生长因子 fas蛋白表达的影响。方法　采用兔离体心脏灌注 (L angendorff)模型 ,2 4只幼兔随机分为 3组 ,对照组 (C,n=8) :仅灌注重碳酸氢盐缓冲液 (KH) 180 min,然后取标本 ;缺血 /再灌组 (I/ R,n=8) :灌注 2 0 min后 ,停灌 4 5 min,复灌 12 0 min;双下肢缺血预处理组 (DL IP,n=8) ,反复 3次阻断双下肢血流 5 m in/放开 5 min,建立L angendorff模型 ,然后重复 I/ R组缺血 /再灌方法。以凋亡细胞原位标记与半定量分析、琼脂糖凝胶电泳检测 DNA片段梯及 bcl- 2、bax、fas基因蛋白的表达作为检查指标。结果　凋亡细胞原位标记与半定量分析 :DL IP组与 I/ R组比较 ,心肌细胞凋亡率明显减少 ;琼脂糖凝胶电泳检测 DNA片段梯 :DL IP组与 I/ R组比较 ,光密度明显增强 ;DL IP组与 I/ R组比较 ,bcl- 2表达明显增多 ,bax、fas表达明显减少。结论　 DL IP通过影响 bcl- 2、bax、fas基因蛋白的表达减少心肌细胞凋亡。

The effects of double limbs ischemic preconditioning on immature myocardial cell apoptosis and expression of bcl-2,bax,fas protein

Objective To investigate the effects of immature myocardial cell apoptosis and expressions of bcl-2,bax,fas protein with double limbs ischemic preconditioning (DLIP). Methods Isolated working rabbit heart model was used in this study. 24 immature rabbits (aged 14～21 days) were divided into 3 groups.Controll group was only perfused Krebs-Henseleit (KH) solution 180 minutes. Ischemia/reperfusion group was perfused 20 minutes ,and then ischemia 45 minutes followed reperfused 120 minutes. DLIP group double limbs were repeatly obstructed/relaxed 3 times,and then repeated the method of ischemia/reperfusion of I/R group. Such index,including the TUNEL, nucleosomal ladder of DNA fragments, and the expression of bcl-2, bax,and fas gene were detected. Results There were markly induction DLIP group than I/R group in TUNEL cell apoptosis, ladder of DNA fragments,expression of bax and fas gene,and increase in expression of bcl-2 gene. Conclusion This study demonstrated that DLIP decrease immature myocardial cell apoptosis by affecting the expression of bcl-2, bax,and fas gene.