异丙肾上腺素预处理对大鼠胰腺移植后缺血再灌注损伤的抑制作用

目的:探讨减轻大鼠胰腺移植后缺血再灌注损伤的保护作用机制.方法:IPC后动态检测大鼠胰腺组织热休克蛋白表达.建立大鼠胰腺移植缺血再灌注模型,选择表达热休克蛋白高峰时段供体大鼠胰腺移植作为实验组,未预处理供体大鼠胰腺移植作为对照组.移植后6 h,采集静脉血及移植胰腺.热休克蛋白70(HSP70)分别用Western blot法及免疫组织化学法检测.免疫组织化学法测定肿瘤坏死因子-α(TNF-α)表达.流式细胞仪检测胰腺细胞凋亡率.碘淀粉比色法检测血淀粉酶水平.结果:IPC后供体大鼠胰腺中HSP70的表达在24 h达到高峰,与其他各时段比较具有显著差异(0.92±0.25 vs 0.24±0.04,0.34±0.06,0.58±0.07,0.62±0.11,0.25±0.09,均P<0.05),IPC后6 h,12 h,24 h,36 h大鼠胰腺中HSP70的表达与未预处理组相应时段比较差异也显著(0.34±0.06 vs 0.28±0.07,0.58±0.07 vs 0.25±0.04.0.92±0.25 vs 0.27±0.05,0.62±0.11vs 0.25±0.06,均P<0.05),48 h恢复到原来水平.而未预处理组各时段间比较差异无统计学意义(P>0.05).HSP70主要表达于胰腺腺泡细胞及血管壁.对照组胰腺组织中TNF-α、细胞凋亡率、中性粒细胞、血淀粉酶的水平明显升高,与假手术组相比差异显著(均P<0.01).实验组降低了胰腺组织中TNF-α、细胞凋亡率、白细胞数、血淀粉酶的水平,与对照组比较差异具有统计学意义(11 929±1220vs46 111±3127,26.7%±4.5%vs 37.4%±4.7%,3 308±531 vs 6668±1506,1057 IU/L±148IU/L vs 1 408 IU/L±195IU/L,均P<0.05).结论:IPC减轻了大鼠胰腺移植后缺血再灌注损伤,IPC保护作用与HSP70的诱导生成有关.

Preconditioning of pancreatic graft with isoproterenol reduces posttransplant ischemia/reperfusion injury in rats

AIM: To determine the protective effects of isoproterenol preconditioning (IPC) against ischemia/reperfusion injury in rats after pancreas transplantation and to explore mechanisms involved. METHODS: The expression of heat shock protein 70 (HSP70) in the pancreas of rats undergoing IPC was detected at different time points after IPC. A rat model of posttransplant pancreatic ischemia/reperfusion injury was established.The donor rats that showed high expression of HSP70 in the pancreas were used as experiment...