Cholecystokinin-8 and proglumide modulation of electrically elicited eating

Electrical stimulation of the lateral hypothalamus (ESLH) elicits eating reliably in satiated animals of many species. The time course of CCK-8 suppression of ESLH induced ingestion has been studied in rats using this central stimulus to elicit eating well beyond limits imposed by the onset of normal satiety in food deprived animals. The reversal of this CCK-8 suppression by the putative CCK-8 antagonist proglumide as well as the effects of proglumide itself upon electrically elicited eating have also been examined. It was found that the suppression of ESLH-induced eating by CCK-8 was potent, rapid in onset, and that its magnitude and duration were dose-related. Other results suggest that proglumide acts as an antagonist of exogenous CCK-8 best at lower doses, as at higher doses it may act as a mixed CCK-8 agonist-antagonist; however, proglumide may also have modulated electrically elicited eating by its effects upon central dopaminergic and/or opioid systems.