缺血后处理对大鼠移植胰腺细胞凋亡的影响

Effects of ischemic postconditioning on graft apoptosis after pancreas transplantation in rats

目的探讨缺血后处理(IPO)对大鼠移植胰腺细胞凋亡的影响及其机制。方法取12只糖尿病SD大鼠随机分为缺血再灌注组(I/R组,n=6)和缺血后处理组(IPO组,n=6),I/R组和IPO组均行胰腺移植。另取12只健康SD大鼠为供体、6只糖尿病SD大鼠为假手术组(对照组);检测各组再灌注前、后血糖;TUNEL法观察移植胰腺组织细胞凋亡情况,W estern B lot检测移植胰腺组织Bax和B cl-2蛋白表达。结果 再灌注后IPO组较I/R组血糖低(P<0.01),移植胰组织中A I值低(P<0.01),IPO组再灌注后移植胰组织Bax蛋白低表达,B cl-2蛋白高表达。结论缺血后处理可以减少移植胰腺缺血再灌注后的细胞凋亡,机制可能与上调B cl-2蛋白和下调Bax蛋白有关。

Objective To evaluate the effects of ischemic postconditioning(IPO) on apoptosis of the graft after pancreas transplantation in rats,and to analyze the possible mechanism.Methods Group Sham which consist 6 normal SD rats underwent sham operation.And 12 steptozozin-induced diabetic SD rats were randomly assigned to 2 groups: Group I/R(ischemic reperfusion) consisting of 6 diabetic rats which received pancreas transplantation normally,without additional intervention,and Group IPO(ischemic postconditioning) consisting of 6 diabetic rats which received pancreas transplantation and postconditioning with 30-second reperfusion followed by 30-second reocclusion for thrice at the onset of reperfusion after cold ischemia.The blood glucose,the apoptotic cells(TUNEL),the expression of Bcl-2 and Bax protein(Western Blot) in the graft were monitored at 2 hours after long-time reperfusion.Results(1) The mean blood glucose level was lower in Group IPO than in Group I/R(P<0.05).(2) The apoptotic index in Group IPO was lower than that in Group I/R(P<0.05),the expression of the Bax protein in Group I/R was higher than that of Group IPO,and the expression of the Bcl-2 protein in Group IPO was higher than that in Group I/R.Conclusion Ischemic postconditioning can reduce apoptosis of the graft,for it may regulate the expressions of Bcl-2 and Bax protein.