An Investigation of the Parameters of CCK-Induced Satiety

Abstract

Two major aspects of CCK-induced satiety were examined in the food deprived sham-feeding rat: the kinetics of the inhibition of feeding produced by CCK and the interaction of CCK-induced satiety with oropharyngeal stimulation. Four results were presented regarding the kinetics of the CCK satiety effect. First, CCk administered coincident with the initiation of sham feeding inhibits feeding in a dose-related manner. Second, the increased efficacy of the higher dose of CCK delivered at the same time as sham feeding results from an increase in the size of maximum suppression and an increase in the time of suppression effected via a decreased latency to suppression. Third, CCk delivered 15 minutes before sham feeding begins has no effect on feeding. Fourth, the administration of a long-lasting derivative of CCK 15 minutes prior to the initiation of sham feeding can suppress intake. Two results were presented regarding the role of oropharyngeal stimulation in CCK-induced satiety. First, it was shown that oropharyngeal stimulation enhances the satiety action of CCK. Second, the amount and pattern of feeding inhibition produced by CCK are equivalent regardless of whether the peptide is administered coincident with, or some time after, the initiation of sham feeding. The implications of these results for the therapeutic use of this peptide and its role in producing satiety are discussed.