Background: Little is known of the effects of hydrocortisone on cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and its counterreceptors (LFA-1, Mac-1) in acute pancreatitis (AP). We investigated the effects of prior treatment with hydrocortisone on the production of ICAM-1 and its counterreceptors (LFA-1 and Mac-1) in AP of rats to clarify the effect of hydrocortisone on induced acute pancreatitis.
Methods: Acute pancreatitis was induced by infusion of 5% chenodeoxycholic acid into the pancreatic duct, followed by ligation of pancreatic duct. Before induction of acute pancreatitis, rats were treated with hydrocortisone (n = 20) or 0.9% saline (n = 20). Blood and specimens from pancreas and lung were obtained from 5 rats from each treatment euthanized at 1 hour or 3 hours, 6 hours, 12 hours. Expression of ICAM-1 was assessed by immunohistochemistry and Western blot analysis of pancreas and lungs. The expression of LFA-1 and Mac-1 on neutrophils was detected by flow cytometer. The therapeutic effect of hydrocortisone was assessed from injuries to pancreas and lung.
Results: ICAM-1 expression in the pancreas of hydrocortisone group was significantly less than in control group at 3 hours and 6 hours. In the lungs of hydrocortisone group, ICAM-1 expression was significantly less than in control group at 3 hours, 6 hours and 12 hours. The expression of LFA-1 and Mac-1 on neutrophils in blood increased significantly in control group over hydrocortisone group. Increased expression of ICAM-1, LFA-1 and Mac-1 preceded leukocyte infiltration. Compared to untreated animals with acute pancreatitis, rats pretreated with hydrocortisone had significantly reduced histological lung injury and output of ascitic fluid.
Conclusions: Prior treatment with hydrocortisone before the induction of acute pancreatitis ameliorates pulmonary injury and the output of ascitic fluid and reduces the expression of ICAM-1 and its counterreceptors (LFA-1, Mac-1) in acute pancreatitis.