Expression of adrenomedullin in hepatic tissue of rats with acute necrotizing pancreatitis associated hepatic injury

Objective To observe the expression of adrenomedullin (ADM) mRNA in hepatic tissue of rats with acute necrotizing pancreatitis (ANP) complicated with hepatic injury.Methods Sixty-four SD rats were randomly divided into control group and ANP group with 32 rats in each group.In ANP group,ANP model was induced by retrograde injection of 5％ sodium taurocholate into biliopancreatic duct of rats.Rats in control group only received sham operation and pancreas manipulation.All the rats were sacrificed at 3,6,12,24 h after the operation.The serum levels of amylase,alanine aminotransferase (ALT),aspartate aminotransferase (AST) and ADM were detected.Pathological changes in pancreatic and hepatic tissue were examined.The expressions of ADM mRNA in hepatic tissue were evaluated by fluorescence quantitative PCR.Results The serum concentrations of amylase,ALT,AST were (7229 ±968),(174.2 ±28.0),(657.7 ± 139.0) U/L,which were significantly higher than those in control group [(2036 ± 292),(104.3 ± 22.1),(419.7 ± 86.3) U/L],and the difference between the two groups was statistically significant (P ＜ 0.05 or P ＜0.01).Pathological injury of pancreas and liver tissue in ANP gradually aggravated with time,and the pathological scores at 12 h were (11.60 ± 1.51),(2.60 ± 0.89),which were significantly higher than those in control group (1.20 ± 0.77,0),and the difference between the two groups was statistically significant (P＜0.01).The serum concentrations of ADM in ANP group increased at 3 h after ANP induction,and reached (38.53 ± 6.25)pg/ml at 12 h,which was significantly higher than that in control group [(28.99 ±3.92)pg/ml] ; the concentrations of ADM in liver tissue increased at 3 h after ANP induction,and reached (3.00 ± 1.49) at 6 h,which was significantly higher than that in control group (1.04 ± 0.20),and the difference between the two groups was statistically significant (P＜0.05 or P＜0.01).Conclusions The expression of ADM mRNA in rat 's hepatic tissue increases in the early stage of ANP,and the serum concentration of ADM also increases. Key words: Pancreatitis,acute necrotizing;  Hepatic insufficiency;  Adrenomedullin