A digestive hormone which was formerly called pancreozymins, secreted by the small intestine.
Cholecystokinin stimulates the contraction in the gallbladder to release bile juice in the intestine.
Cholecystokinin also stimulates the release of pancreatic juice from the pancreas in the stomach and may cause satiety (a state of feeling fullness).
It is believed that meal-induced cholecystokinin secretion activates the satiety center (region of the brain which regulates the intake of food) of the brain so that person feels full and stops eating food.
The secretion of cholecystokinin is stimulated by the release of hydrochloric acid, amino acids, and fats into the stomach or duodenum.