VOLUNTARY INTAKE AND GASTRIC-EMPTYING IN PIGS - EFFECTS OF FAT AND A CCK INHIBITOR

The influence of the cholecystokinin (CCK) antagonist MK-329 (0.1 mg/kg) on short-term control of voluntary food intake and gastric emptying was studied in five pigs. Arterial injection of MK-329 abolished the inhibition of intake resulting from duodenal infusion of emulsified fat (Intralipid, 24 g/h). However, MK-329 only reduced the inhibition of dry matter (DM) and liquid emptying, and hence increased stomach volume at satiety. Intralipid infusion decreased the rise in gastric pressure during feeding. All these changes are consistent with endogenous CCK, released by Intralipid, inhibiting intake independent of the concomitant slowing of gastric emptying. MK-329 alone significantly increased intake using two different diets, but had no effect on gastric emptying, so that gastric volume at satiety was significantly increased. These results suggest that endogenous CCK may be part of short-term satiety control in the pig.