ABSTRACT
Objective To investigate the effects of intermittent hypoxic preconditioning on residual liver regeneration after parital hepatectomy in rats.Methods Fifty-four Sprague-Dawley rats were randomly divided into 3 groups (each group contained eighteen animals):sham operation group (SO group),parital hepatectomy group (PH group)and intermittent hypoxic preconditioning group (IHP group).The rats in PH group underwent the left and middle lobectomy of liver(70％ hepatectomy).The rats in IHP group were exposed to hypoxic environment of 10％ oxygen for 1 h/d.And after a week,the rats underwent parital hepatectomy.Six rats in each group were sacrificed respectively on postoperative day 1,3 and 5 (POD 1,3 and 5).The resected liver and the regenerated liver were weighed to calculate liver regeneration degree and regeneration index.The values of alaninea minotransferase (ALT) and aspartate aminotransferase (AST) in the inferior vena venous blood were examined by automatic biochemical analyzer.The positive ratio of hepatocellular proliferating cell nuclear antigen (PCNA) in the residual liver was investigated immunohistochemically.Results The degree and index of liver regeneration in IHP group were respectively higher than those in PH group on POD 1 and 3(P ＜0.05),but there were no statistical differences between the two groups on POD 5.The levels of ALT and AST in PH and IHP group began to decline after surgery,but they remined higher than those in SO group.Moreover,the ALT and AST levels in IHP group were significantly lower than those in PH group on POD 1 (P ＜0.05).The positive ratios of hepatocellular PCNA were respectively higher than those in SO and PH group on POD 1,3 and 5 (P ＜ 0.05).Conclusions To some extent,preoperative intermittent hypoxic preconditioning could prevent hepatocellular damage after parital hepatectomy,what is more,it also could promote the remnant liver regeneration.But the mechanism still needs to be studied furter.