Beneficial effect of pancreatic polypeptide in experimental pancreatitis

Two animal models have been employed to examine the role of pancreatic polypeptide, a potent and selective inhibitor of pancreatic exocrine secretion, in the treatment of acute pancreatitis. In one model pancreatitis was induced by feeding young female Swiss Webster mice an ethionine-supplemented, choline-deficient diet for 48 hr. Animals (N = 30 per group) were injected subcutaneously every 8 hr for 7 days with pancreatic polypeptide (0, 2, 20, and 200 micrograms/kg/day). Treatment with 20 and 200 micrograms/kg/day pancreatic polypeptide significantly (P less than 0.05) reduced mortality from a control rate of 70% to 42% and 33%, respectively. Treated animals also exhibited significant (P less than 0.05) decreases in pancreatic content of activated chymotrypsin and an improvement in pancreatic histology. Pancreatic polypeptide was effective whether treatment was started before or at the same time the test diet was introduced. In contrast, pancreatic polypeptide failed to protect dogs with acute pancreatitis induced by retrograde injection of the pancreas with bile, which may reflect the rapid and mechanical nature of pancreatic damage in this animal model.