Acute pancreatitis is a real medical problem with high patients mortality. Pathogenic interdependence between pancreas follicles function and islet endocrine secretion is under research. PP cells are pancreatic polypeptide (PP) producing cells, they determine about 1% islets, but their function is not completely known yet. Vagus nerve and peptidergic stimulation regulates PP secretion.
The aim of study was to estimate cerulein induced pancreatitis effects on rat serum PP concentration and pancreas morphology characteristics.
The study was conducted on male Wistar rats. They were anaesthetized with ketamine. We measured serum PP concentration during experimental cerulein-induced acute pancreatitis and different inflammatory process regression stages. Acute pancreatitis was developed through i.v. cerulein infusion 5 μg/kg per hour. Rats were divided into several groups in dependence on infusion time 3,6,9,12 hours. Then rats had free access to standard nourishment and water. Blood samples from rat group with 12 hours cerulein infusion were taken after 3,6,9 and 12 days of observation. Control groups received i.v. 0.9% NaCl infusion. Pancreas histological changes were analyzed. Serum amylase and PP concentrations were assessed with DRG International Inc. (USA) kit. Both rabbit serum with antibodies against PP and goats anti-rabbit gamma-globulin in buffer were used.
After 12 hours lasting cerulein infusion we obtained full biochemical and morphological acute pancreatitis picture. These changes start to regress after cerulein infusion withdrawal. Serum PP concentration was decreased after 3 hours of cerulein infusion, still decreased until the end of infusion (0.99 pg/ml). After cerulein cessation, progressive PP increase was observed, attained control PP concentration after 9 days (2.4 pg/ml) and exceed it after 12 days (3.5 pg/ml).
Cerulein significantly influence on serum PP concentrations - decreases it during pancreatitis induction and increases in regression stage. PP determines exocrine function stimulation, correlates with tissue destruction degree and pancreas enzymes disturbances.