Effect of hypoxic precondition on apoptosis of hepatic ischemia reperfusion with the hepatectomy of transplanted hepatic cancer models in SD rants / 国际外科学杂志

ABSTRACT

Objective To investigate the effect of Heat shock protein 70 induced by hypoxic precondition on apoptosis of the remnant livers after the hepatectomy of transplanted hepatic cancer models in SD rants and it's possible mechanisms.Methods Sixty SD rats of transplanted hepatic cancer models were divided into group A (sham operation group),group B (IR + hepatectomy group),and group C (hypoxia precondition + IR + hepatectomy group),with 20 rats in each group.C group was given 10％ oxygen atmosphere for 90 minutes before operation,In 15 minutes of hepatic vascular occlusion with pringle method,Left lateral of liver which tumor was located was resected.At 1,8,12,24 hours after operation,Five rats of each group were killed respectively,then the remnant liver tissues were sampled to measured the hepatocytes apoptosis rate with flow cytometry,expression of heat shock protein 70 (HSP70) and Bax were detected by Western blotting.The serum AST and ALT activities were measured by an automatic analyzer.The histological changes of the hepatocytes were also observed by optical microscopy.All the data were statistically analyzed.Results (1) Compared with A and B group,the HSP70 expression increased obviously in C group at each time point (all P ＜ 0.05).The protein showed a weak expression in group A and B group,while the index had no significant differences between two groups (P ＞ 0.05).(2) In B group compared with A group,the expression of Bax and the hepatocytes apoptosis rate were significantly increased (all P ＜ 0.01 or P ＜0.05).However,amplitudes of the above changes in C group were significantly lower than those of B group (all P ＜ 0.05).(3)The liver function was improved in group HP.The pathological examination showed that the liver tissues in A group were general normal and in C group were showed mild changes,but in B group presented evident pathological changes.Conclusions HP can protect against ischemia-reperfusion injury after the hepatectomy of transplanted hepatic cancer models in SD rants,one of possible mechanisms is that HP can induce HSP70 expression at great intensity,which may decrease expression of Bax protein and the apoptosis of hepatocytes.