ENDOGENOUS CHOLECYSTOKININ IN THE CONTROL OF GASTRIC-EMPTYING OF LIQUID NUTRIENT LOADS IN RHESUS-MONKEYS

A role for the brain/gut peptide cholecystokinin (CCK) in the control of gastric emptying has been proposed. In the present studies, we have used a potent type A CCK-receptor antagonist (devazepide) to examine the quantitative contribution of endogenously released CCK in the cont rol of liquid gastric emptying of 100 ml lipid, protein, and carbohydr ate test loads in rhesus monkeys. Emptying was studied in conscious mo nkeys equipped with chronic indwelling gastric cannulas. Prior intraga stric administration of devazepide (1.0-320 mug/kg) differentially aff ected the 10-min emptying of glucose (0.125 g/ml), peptone (4.5%), and Intralipid (4.5%). Glucose emptying was not affected by any dose of t he CCK antagonist. The emptying of peptone was accelerated by doses of 10 mug/kg or higher. This effect, however, was only partial and plate aued at a dose of 100 mug/kg. The gastric emptying of Intralipid was a ccelerated at a dose of 32 mug/kg, and the inhibitory effect of the In tralipid was completely eliminated at a dose of 320 mug/kg. At this do se of devazepide, the Intralipid test meal emptied from the stomach at the same rate as physiological Wine. These data demonstrate that in r hesus monkeys endogenously released CCK 1) does not play a role in the control of glucose emptying, 2) is a partial mediator of the inhibito ry action of peptone on gastric emptying, and 3) is the primary inhibi tory mediator in the control of the gastric emptying of Intralipid.