Melatonin post-intervention could promote the expression of thioredoxin-1 in rats pancreatic tissues with acute necrotizing pancreatitis

Objective To investigate the effect of melatonin post-intervention on the expression of thioredoxin-1(TRX-1) in rats with acute necrotizing pancreatitis(ANP).Methods Male Spraque-Dawley rats were randomly allocated to control group,ANP group,melatonin post-intervention group with 24 rats in each.The rats in ANP group received three intraperitoneal injections of 25 mL/kg 6% L-arginine at an interval of 1 h to induce ANP.The rats in melatonin post-intervention group received intraperitoneal injections of 20 mL/kg 0.25% melatonin after ANP induction.Rats in control group received intraperitoneal injections of same amount of saline.Rats were sacrificed at 6,12 and 24 h after ANP induction.The pathological evaluation of pancreatic tissues was performed.The concentrations of malondialdehyde and myeloperoxidase in pancreatic tissues were measured.The serum level of TRX-1 was measured by ELISA.The expressions of thioredoxin-1 and thioredoxin-1 mRNA in pancreatic tissueswere confirmed by immunohistochemistry and RT-PCR,respectively.ResultsComparerd to the control group,pathological scores,malondialdehyde,and myeloperoxidase of pancreatic tissues in ANP group were significantly increased(P0.05),while were significantly lower in melatonin post-intervention group(P0.05).Comparerd to the control group,serum TRX-1 contents in ANP group significantly decreased(P0.05) at 6 and 12 h points,while were significantly higher in melatonin post-intervention group(P0.05) than those in ANP group.the peak value of TRX-1 protein and TRX-1 mRNA expressions in pancreatic tissues shifted from 12 h after ANP induction in ANP group to 6 h after ANP group in melatonin post-intervention group.Conclusion Melatonin post-intervention reduces the injury of pancreatic tissue through increased tissue and serum TRX-1 levels in ANP rats.