Role of endogenous CCK in the inhibition of gastric emptying by peptone and Intralipid in rats

To assess the role of endogenous cholecystokinin in the control of gastric emptying of peptone solutions and Intralipid suspensions, we examined the a bility of a dose range of the CCK-A antagonist, devazepide to accelerate th e gastric emptying of various caloric concentrations of peptone and Intrali pid in rats. In the absence of devazepide, both peptone and Intralipid empt ying slowed with increasing concentration. Devazepide's effect on peptone g astric emptying diminished with increasing peptone concentration. The thres hold dose for accelerating the emptying of 0.2 kcal/ml peptone was lower th an the threshold dose for affecting 0.5 kcal/ml peptone and devazepide had no effect on the gastric emptying of 1.0 kcal/ml peptone. In contrast, deva zepide affected Intralipid gastric emptying at all three Intralipid concent rations and the threshold dose decreased with increasing Intralipid concent ration. However, the magnitude of the effect of devazepide on peptone or In tralipid gastric emptying was partial and did not increase as a function of concentration. These data demonstrate a role for endogenous CCK in the emp tying of peptone and Intralipid but suggest that endogenous CCK does not ac count for the increased slowing of gastric emptying evident with increased caloric concentration (C) 2000 Elsevier Science B.V. All rights reserved.