Effect of adrenocorticotropic hormone on pure exocrine pancreatic secretion in man.

The effect of adrenocorticotropic hormone (ACTH) on pure exocrine pancreatic secretion was studied in 7 subjects with external transduodenal drainage of the main pancreatic duct performed after biliary tract surgery. Intravenous injection of 0.25 mg of ACTH during a prolonged intravenous infusion of secretin (0.5 clinical units per kg-hr) plus cholecystokinin (0.5 Ivy dog units per kg-hr) significantly reduced protein and lipase (both concentration and output) without affecting volume and bicarbonate secretion. The reduction appeared soon after ACTH injection (peak inhibition in the first 15-min period) and lasted about 75 min. The adrenocortical response to ACTH reached its peak at the 60th min. The mechanism by which the pituitary hormone selectively inhibits pancreatic enzyme secretion without affecting volume and bicarbonate remains to be clarified.