Cholecystokinin 7 (CCK7)

CCK-7 increased the gall-bladder pressure and decreased the gastric pressure following i.v. infusion in conscious dogs. In small intestine and Heidenhain pouch CCK-7 exerted an initial excitatory effect followed by an inhibitory effect on intraluminal pressure and peristalsis. In all organs the effect of CCK-7 on pressure was correlated with a change of spike discharge. CCK-7 is more potent on gastrointestinal motor activity than a Boots preparation of pancreozymin. CCK-7 at doses within the physiological range could be involved in the regulation of gastrointestinal motility.

Two peptides that interact exclusively with peripheral-type CCK receptors are the heptapeptide COOH-terminal fragment from CCK (CCK-7) and the analogous sequence from cerulein (CER-7) in which threonine replaces the methionine proximal to the NH2 terminus.