ABSTRACT
Objective To observe the expression of ghrelin and growth hormone secretagogue receptor (GHSR) in pancreas of rats with acute necrotizing pancreatitis (ANP),and investigate the role of ghrelin in the pathogenesis of ANP.Methods Seventy SD rats were randomly divided into ANP group (n =35) and control group (n =35).ANP model was induced by retrograde injection of 4％ sodium taurocholate into the biliary and pancreatic duct.Rats in the control group underwent laparotomy with gentle pancreas manipulation only.At 3,6,12,24,48 h after ANP induction,the rats were sacrificed,and the serum level of amylase was determined,pathological changes in pancreatic tissue were routinely observed and scored.The expressions of ghrelin mRNA,protein and GHSR mRNA,protein in pancreas were evaluated by RT-PCR and Western blot.Results Serum amylase level began to increase at 3h after sodium taurocholate injection and reached the peak value at 6 h [(8244 ± 2950) U/L],which was significantly higher than that in control group (P ＜ 0.05).Pancreatic injuries was aggravated with time,the pathologic score at 24 h was (11.91 ± 1.31) score,which was significantly higher than (3.12 ± 1.60) score in the control group.The expressions of ghrelin mRNA and GHSR mRNA in pancreas of ANP group were increased gradually with time,and were significantly higher than those of control group at all time points,at 48 h,1.29 ±0.64 vs 0.58 ±0.05 and 0.94 ±0.16vs 0.19 ±0.03,P ＜ 0.05.The expressions of ghrelin protein and GHSR protein in pancreas of ANP group were significantly higher than that in control group at 12,24,48 h.at 48 h,3.05 ± 0.48 vs 2.18 ± 0.23 and 2.34 ± 0.32 vs 1.55 ± 0.10 (P ＜ 0.05).Conclusions The expressions of ghrelin mRNA,protein and GHSR mRNA,protein of pancreas are significantly increased in rats of ANP,and are associated with the severity of ANP.