Expression Of High Mobility Group Box 1 Protein And Toll-like Receptor 4 In The Pancreas And The Liver Tissue Of Rats With Severe Acute Pancreatitis And The Intervention Effect Of Ulinastatin

Objective:To investigate the inflammatory factor expression of high mobility group box 1 protein(HMGB1)and Toll-like receptor 4(TLR4)in the pancreas and HMGB1 in the liver tissue of rats with severe acute pancreatitis(SAP)and the intervention effect of ulinastatin.Methods:The 54 Spragye-Dawley rats were randomly divided into three groups:control group,severe acute pancreatitis(SAP)group and ulinastatin treatment group.Then every group was divided into three groups:6 hours(6h),12h and 24h(each group n=6).The Pancreas of the control group were just flipped gently after the abdomen incision had been performed.The SAP and the ulinastatin treatment groups were induced by 5%sodium taurocholate injection under the pancreatic membrane.The treatment groups were injected ulinastatin via the tail vein after the operation.The pancreatic tissues were dyed with haematoxylin-eosin and evaluated by according to the improved Schmidt’s standard:the serum amylases were detected by 4,6-ethyliden-(G7)-p-nitrophenyl(G 1)-a-D-mal-topentaoside(EPS-G7)method.The protein concentrations of HMGB1 in the blood Serum and pancreatic tissue were detectded by enzyme linked immunosorbent assay(ELISA).The levels of HMGB1 and Toll-like receptor 4(TLR4)expression in pancreatic tissue were determined with Envision two-steps immunoassay.The Aspartate aminotransferase(AST)and Alanine aminotransferase(ALT)levels in the blood Serum were measured by rate method.HMGB1 mRNA expression in the liver tissue was measured with reverse transcriptase-polymerse chain reaction(RT-PCR).Results:1.Compared with the control group,amylase and pathological changes in the SAP group and the treatment group were increased remarkably at each time point after operation,The difference was statistically significant(P<0.01),so the SAP model was successfully established.2.Compared with the control group,the protein concentration of HMGB1 in the blood Serum and pancreatic tissue in the SAP group were increased significantly at 6 h and rapid upstroke at 12 h,and maintained at high levels up to 24h after operation(P<0.01).Compared with the SAP group,the protein concentration of HMGB1 in the blood Serum and pancreatic tissue in the treatment group obviously decreased at the same time piont(P<0.01).3.TLR4 expression in pancreatic tissue began to increase at 6h,and reached the peak at 12h,and began to decline at 24h in the SAP group.It was remarkablely higher compared with the the control group at the same time point(P<0.01).Compared with the SAP group,TLR4 expression in pancreatic tissue in the treatment group was significantly decreased at the same time piont(P<0.01).4.HMGB1 expression in pancreatic tissue began to increase at 6h,and rise rapidly at 12h,and kept markedly higher at 24h in the SAP group.It was significantly higher compared with the control group(P<0.01).Compared with the SAP group,HMGB1 expression in pancreatic tissue in the treatment group was significantly decreased at the same time piont(P<0.01).5.The levels of AST and ALT in the blood Serum in the SAP group and the treatment group were higher than those in the control group at the same time point(P<0.01);but those in the treatment group were significantly reduced than in the SAP group and higher than those in the control group(P<0.01).6.HMGB1 mRNA was a certain extent expression in liver tissue in the control group.HMGB1 mRNA in the SAP group was obviously higher than the control group.HMGB1 expression started to strengthen from 6h,and continued to rise at 24h in the SAP group,Compared with the SAP group,it was outstandingly lower in the ulinastatin treatment group(P<0.05).Conclusion:1.The SAP model was successful.2.HMGB1 could contribute to the pathogenesis in the pancreatic tissue of rats with severe acute pancreatitis by combining with its cell-surface receptor TLR4.3.Ulinastatin probably played a protective role against pathogenesis by intervening HMGB1,TLR4 signaling pathway in the pancreatic tissue of rats with severe acute pancreatitis.4.Ulinastatin had therapeutic effect on SAP liver damage which were mediated by the HMGB 1.