Inhibition of Cholecystokinin Response in the Gallbladder by Dibenamine and Its Protection by Benzodiazepines

Abstract

The contractile response of the guinea-pig gallbladder to cholecystokinin (CCK) and acetylcholine (ACh) was irreversibly inhibited by 5×10^-5 M dibenamine, and the dibenamine-induced inhibition in the CCK response was prevented by 10^-4 M chlordiazepoxide (CDP) and diazepam (DZP), but not by 10^-2 M proglumide or 10^-6 M atropine. The dibenamine-induced inhibition in the ACh response was prevented by 10^-6 M atropine, but not by 10^-4 M CDP. These findings suggest that the binding of CCK to the CCK receptor can be inhibited by benzodiazepines.