热休克预处理对大鼠胰腺移植后缺血再灌注损伤的抑制作用

Heat Shock Preconditioning on Pancreas Graft Induced Posttransplant Ischemia-Reperfusion Injury in Rats

目的:探讨热休克预处理(HPC)减轻大鼠胰腺移植后缺血再灌注损伤的机制。方法:热休克预处理后动态检测大鼠胰腺组织热休克蛋白(HSP)表达。建立大鼠胰腺移植缺血再灌注模型,热休克预处理后12h的供体大鼠胰腺移植作为实验组,未预处理的供体大鼠胰腺移植作为对照组。胰腺移植后6h检测静脉血及移植胰腺。Western blot法检测胰腺组织中HSP70的表达,免疫组化法测定肿瘤坏死因子(TNF)-α表达。碘淀粉比色法检测血淀粉酶水平。光镜观察胰腺病理改变。结果:HPC后供体大鼠胰腺中HSP70的表达在12h达到高峰,与其他各时间点比较差异均有统计学意义,与未预处理组比较亦有统计学意义(P<0.05或P<0.01),48h恢复到原来水平。胰腺组织中TNF-α、白细胞浸润及血淀粉酶水平检测结果显示,对照组较假手术组明显升高,实验组较对照组降低,差异均有统计学意义(P<0.05或P<0.01)。实验组胰腺间质水肿及出血明显轻于对照组。结论:热休克预处理可以减轻大鼠胰腺移植后缺血再灌注损伤,热休克预处理的延迟保护作用与HSP70的诱导生成有关。

Objective：To investigate the effects of heat shock precondition （HPC） on pancreas transplantation induced ischemia-reperfusion injury in rats,and the mechanisms thereof. Methods：The rat models of ischemia-reperfusion injury after pancreas transplantation were set up. Expression of heat shock protein70 （HSP70） was detected at different times in pancreas of rat models of HPC. Donator rats with HPC after 12 hours were regarded as experiment group for pancreas transplantation, and donator rats without HPC as control group. The samples of blood and pancreas were examined after pancreas transplantation for 6 hours in rats. The levels of HSP70 expression in pancreas were examined with Western-blotting. The levels of TNF-α in pancreas were detected with immunohistochemistry. The levels of hemodiastase were determined with iodoamylum chromatometry. Pathological changes of pancreas were detected with microscope. Results：The expression of HSP70 in pancreas of donator rats achieved peak after HPC 12 hours, which was significant different compared with that of other time points （P 0.05）, and was significant different compared with that of no HPC group （P 0.01）. The level of HSP70 expression was recovered to the normal level after HPC 48 hours. Levels of TNF-α, leukocyte and hemodiastase were significantly increased in pancreas of control group compared with those of sham group （P 0.01）. Levels of TNF-α, leukocyte and hemodiastase were significantly decreased in pancreas of experiment group compared with those of control group （P 0.05）. The interstitial edema and hemorrhage of pancreas were reduced in experiment group than those of control group. Conclusion：Heat shock preconditioning reduced ischemia-reperfusion injury in rat model after pancreas transplantation. The mechanism of delaying protective effect after HPC correlated with production of HSP70.