Cholecystokinin is a hormone of protein origin that participates in the alimentary canal for breaking down the polypeptides and lipids. This chemical messenger is secreted by the small intestine itself in its duodenum section containing cell called enteroendocrine cells. Generally, this hormone stimulates the pancreas and gall bladder to release their digestive juices into the small intestine. The gall bladder produces bile juices containing salts like sodium taurocholate and sodium glycocholate.