On the tissue-specific processing of procholecystokinin in the brain and gut--a short review.

Cholecystokinin (CCK) is a major peptide hormone in the gut and a major peptide transmitter in the brain. Its synthesis requires endoproteolytic cleavage of proCCK at several mono- and dibasic sites by prohormone convertases (PCs). Of these, PC1 and PC2 are expressed in cerebral neurons and intestinal endocrine cells.