Abdominal vagal mediation of the satiety effects of exogenous and endogenous cholecystokinin in rats.
The hypothesis that peripherally administered cholecystokinin C-terminal octapeptide (CCK-8) and endogenous CCK act by the same abdominal vagal mechanism to produce satiety was tested by injecting rats with CCK-8 or the type A CCK receptor antagonist MK-329 after they had received bilateral subdiaphragmatic vagotomies. CCK-8 (8 nmol/kg ip) inhibited 1-h food intake by 60%; vagotomy and MK-329 (0.5 mg/kg sc) each completely blocked this effect. In contrast, vagotomy did not alter the stimulatory effect of MK-329 (0.5 mg/kg sc) on feeding; 3-h cumulative intake in control and vagotomized animals was increased by 25 and 34%, respectively. These results suggest that satiety is mediated in part by an endogenous CCK action that is independent of abdominal vagal innervation.
Reidelberger
R D
RD
Department of Veterans Affairs Medical Center, Omaha, Nebraska 68105.
D000005:Abdomen / Q000294:innervation; D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology; D002766:Cholecystokinin / Q000037:antagonists & inhibitors / Q000502:physiology*; D020109:Devazepide; D004435:Eating / Q000187:drug effects; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012528:Satiety Response / Q000187:drug effects / Q000502:physiology; D012844:Sincalide / Q000494:pharmacology*; D014628:Vagotomy; D014630:Vagus Nerve / Q000502:physiology*
D001570:Benzodiazepinones; D002766:Cholecystokinin; D020109:Devazepide; D012844:Sincalide