Study on inhibition of pancreatic exocrine secretion by somatostatin in rats

We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion. Somatostatin immunoneutralization increased both the total amylase and volume of pancreatic secretion. Cholecystokinin-A receptor antagonism abolished the stimulatory effect of somatostatin immunoneutralization. We conclude that somatostatin tonically inhibits, pancreatic secretion in fasted rats via inhibition of the release or action of cholecystokinin. Furthermore, the source of these peptides is likely islet delta cells and intrapancreatic neurons, respectively.