Duocrinin is a gastrointestinal hormone that is secreted within the intestine and stimulates the secretory activity of the duodenal glands (Brunner glands).
Cholecystokinin is synthesized by the cells of the mucosal epithelium of the small intestine and secreted in the duodenum. It causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively
