Description
A-57696 is a cholecystokinin antagonist. It is selective for cortical CCK-B receptors (IC50 = 25 nM), compared with pancreatic CCK-A receptors (IC50 = 15 microM). It is a competitive antagonist in reversing CCK8-stimulated pancreatic amylase secretion and phosphoinositide breakdown. A-57696 behaved as a partial agonist in stimulating calcium mobilization at CCK-B/gastrin receptors.
Uses
A-57696 is a cholecystokinin antagonist with selective activity at cortical CCK-B receptors (IC50 = 25 nM). A-57696 behaves as a competitive antagonist in reversing CCK8-stimulated pancreatic alpha-amylase secretion and phosphatidylinositol degradation. A-57696 fails to induce gallbladder contraction and inhibits CCK8-induced contraction. A-57696 behaves as a partial agonist at CCK-B/gastrin receptors on NCI-H345 cells, achieving 80% of the maximal CCK8 response. A-57696 and CCK8 inhibit each other in a calcium mobilization assay[1].
References
[1] Distinct requirements for activation at CCK-A and CCK-B/gastrin receptors: studies with a C-terminal hydrazide analogue of cholecystokinin tetrapeptide (30-33) PMID:2601685
