Cholecystokinin (CCK) is a peptide hormone discovered in the small intestine. Together with
secretin and gastrin, CCK constitutes the classical gut hormone triad. In addition to
gallbladder contraction, CCK also regulates pancreatic enzyme secretion and growth,
intestinal motility, satiety signalling and the inhibition of gastric acid secretion. CCK is,
however, also a transmitter in central and intestinal neurons. Notably, CCK is the most
abundant neuropeptide in the human brain. Owing to difficulties in developing accurate …