| Abstract: | AIM: Pancreatic regenerating protein (reg Ⅰ) stimulates pancreatic regeneration after pancreatectomy and is mitogenic to ductal and β-cells. This suggests that reg Ⅰ and its receptor may play a role in recovery after pancreatic injury. We hypothesized that reg Ⅰ and its receptor are induced in acute pancreatitis.METHODS: Acute pancreatitis was induced in male Wistar rats by retrograde injection of 3% sodium taurocholate into the pancreatic duct. Pancreata and serum were collected 12, 24, and 36 hours after injection and from normal controls (4 rats/group). Reg Ⅰ receptor mRNA, serum reg Ⅰ protein, and tissue reg Ⅰ protein levels were determined by Northern analysis, enzymelinked immunosorbent assay (ELISA), and Western analysis, respectively. Immunohistochemistry was used to localize changes in reg Ⅰ and its receptor.RESULTS: Serum amylase levels and histology confirmed necrotizing pancreatitis in taurocholate treated rats. There was no statistically significant change in serum reg Ⅰ concentrations from controls. However,Western blot demonstrated increased tissue levels of reg Ⅰ at 24 and 36 h. This increase was localized primarily to the acinar cells and the ductal cells by immunohistochemistry. Northern blot demonstrated a significant increase in reg Ⅰ receptor mRNA expression with pancreatitis. Immunohistochemistry localized this increase to the ductal cells, islets, and acinar cells.CONCLUSION: Acute pancreatitis results in increased tissue reg Ⅰ protein levels localized to the acinar and ductal cells, and a parallel threefold induction of reg Ⅰ receptor in the ductal cells, islets, and acinar cells. These changes suggest that induction of reg Ⅰ and its receptor may be important for recovery from acute pancreatitis. |
