We have reported previously that the transmembrane domains of the cholecystokinin-B/gastrin receptor (CCK-BR) comprise a putative ligand binding pocket. In the present study, we examined whether amino acid substitutions within the CCK-BR pocket altered the affinities and/or functional activities of L-365,260 (the prototypical nonpeptide CCK-BR antagonist) and two structural derivatives, YM022 (...

We studied the effect of cholecystokinin (CCK) and the octapeptide of cholecystokinin (OP-CCK) on the feline gallbladder and sphinecter of Oddi. Both CCK caused a dose-dependent gallbladder contraction and sphincter of Oddi relaxation. The half-maximal responses of the sphincter of Oddi were 6 ng/kg for OP-CCK and 0.15 Ivy-dog U/kg for CCK, which were lower than those of the gallbladder with 28...

Cholecystokinin (CCK) and gastrin are vertebrate brain-gut peptides featured by a sulfated tyrosine residue and a C-terminally amidated tetrapeptide consensus sequence. Cionin, identified in the ascidian, Ciona intestinalis, the closest species to vertebrates, harbors two sulfated tyrosines and the CCK/gastrin consensus tetrapeptide sequence. While a putative cionin receptor, cior, was cloned, ...

Gastrin gene expression exhibits a complex pattern of tissue-specific expression during the neonatal development of the gastrointestinal tract and pancreas. In the rat fetus, the pancreas is the major site of gastrin expression; very little gastrin is found in the antrum which is the major site of adult expression. Pancreatic gastrin mRNA is identical to the antral species having the same trans...

A wealth of data supports the idea that the stomach and cholecystokinin octapeptide (CCK-8) normally play important roles in meal size and satiety. We studied long-term gastrectomized humans to further evaluate this possibility. Ten humans, who were gastrectomized 8 (3-12) years earlier, and eight controls ate a meal from a plate placed on a scale connected to a computer and estimated their sat...