大鼠肝脏热缺血-再灌注损伤中HSP 72对肝细胞的保护作用

The Protective Effect of Heat Shock Protein 72(HSP 72) on Hepatocyte in Rat Hepatic Warm Ischemia Reperfusion Injury

目的探讨应用亚砷酸钠(Sodium Arsenite,SA)诱导热休克蛋白72(HSP 72)在大鼠肝脏热缺血-再灌注损伤中对肝细胞的保护作用。方法采用大鼠肝脏部分热缺血-再灌注模型,预先给予SA(6mg/ml),24h后阻断肝脏中、左叶血供90min,再灌注3、6h,分别用Westernblot检测肝脏中的热休克蛋白72(HSP72)、核转录因子-κB(NF-κB);外周血测定ALT、AST、LDH、TNF-α、CINC、MIP-2;组织学作HE染色、HSP72、NF-κB免疫组化。观察7d存活率。结果Westernblot结果显示SA组均有HSP72表达,对照组则无表达。对照组有NF-κB表达,SA组则无表达。SA组血清ALT、AST、LDH、TNF-α、CINC、MIP-2均显著低于对照组(P<0.05)。病理观察结果显示,对照组可见肝实质细胞浊肿、空泡样变性、肝窦内中性粒细胞浸润。SA组肝实质细胞无明显损伤。免疫组化结果显示,SA组肝细胞胞浆、核均有较显著的HSP72表达,对照组基本无表达。对照组肝实质细胞核内有较显著的NF-κB的表达,SA组则基本无表达。SA组7d生存率为87.5%(7/8),显著高于对照组的37.5%(3/8)(P<0.05)。结论SA可诱导大鼠肝脏产生HSP72,在肝脏热缺血-再灌注中抑制NF-κB的活性,减轻肝脏炎症反应,对肝实质细胞具有保护作用。

Objective To study the protection of heat shock protein（ HSP 72） induced by Sodium Arsenite（SA） for hepatic parenhymal cells in hepatic warm ischemia reperfusion injury in rat. Methods Partial hepatic warm ischemia-reperfusion model was used by damping the blood flow to the left and median lobes. After 90 minutes of warm ischemia, the blood flow was restored. Blood and tissue sampling was collected at 3 and 6 hours after reperfusion. 24 hours before hepatic iscbemia, SA was injected at a dose of 6 mg per kg body weight in SA group. Expression of lISP 72 and NF-κB was observed with Western blot; ALT, AST, LDII, TNF-α, CINC, MIP-2 were determined in peripheral blood; routine liE and immunohistochemical staining for HSP 72 NF-κB were examined. The survival rate of 7 days was observed. Results In 3- and 6- hour reperfusion after 90 minutes warm ischemia, significant expression of lISP 72 was observed in group SA but not in control group; in contrast, significant expression of NF-κB was observed in control group but not in group SA. Serum ALT, AST, LDII, TNF-α, CINC, MIP-2 also descended significantly in group SA compared with group NS（ P〈0.05）. Hepatic damage was alleviated notably in histological staining. Pathological study showed that ballooning, vacuolar denaturalization, coagulative necrosis in hepatocyte and neutrophilic infiltration were found in control group but not in SA group. Immunohistochemical study showed that lISP 72 was expressed significandy in both nucleus and cytoplasm of hepatocytes in SA group and was faint in control group. But NF-κB was markedly expressed in nucleus of hepatocytes in control group and was not in SA group. Conclusion These data suggested that the inducible expression of HSP 72 by SA may counteract hepatic warm ischemia reperfusion injury and may provide cytopretection for hepatocytes. HSP 72 can control the inflammatory reaction in hepatic warm ischemia reperfusion by preventing the activation of NF-κB.