title: Cholecystokinin-33, but not cholecystokinin-8 shows gastrointestinal site specificity in regulating feeding behaviors in male rats.
abstract: Two separate experiments were performed to localize the gastrointestinal sites of action regulating meal size (MS), intermeal interval (IMI) length and satiety ratio (SR, IMI/MS) by cholecystokinin (CCK) 8 and 33. Experiment 1: CCK-8 (0, 0.05, 0.15, 0.25nmol/kg) was infused in the celiac artery (CA, supplies stomach and upper duodenum) or the cranial mesenteric artery (CMA, supplies small and part of the large intestine) prior to the onset of the dark cycle in free feeding, male Sprague Dawley rats and MS (normal rat chow), IMI and SR were recorded. Experiment 2: CCK-33 (0, 0.05, 0.15, 0.25nmol/kg) were infused in the CA or the CMA, under the same experimental conditions above, and MS, IMI and SR were recorded. Experiment 1 found that CCK-8 reduces MS, prolongs the IMI and increases the SR at sites supplied by both arteries. Experiment 2 found that CCK-33 reduces MS and increases the SR at sites supplied by the CMA. We conclude that in male rats the feeding behaviors evoked by CCK-33, but not CCK-8, are regulated at specific gastrointestinal sites of action.
authors: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA.
authors: Martha C
authors: MC
authors: Washington
authors: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA.
authors: Thaer R
authors: TR
authors: Mhalhal
authors: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA. Electronic address: sayeghai@mytu.tuskegee.edu.
authors: Ayman I
authors: AI
authors: Sayegh
mesh_terms: D000818:Animals; D002445:Celiac Artery / Q000187:drug effects / Q000502:physiology; D002766:Cholecystokinin / Q000494:pharmacology*; D004435:Eating / Q000187:drug effects / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects* / Q000502:physiology; D041981:Gastrointestinal Tract / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009928:Organ Specificity / Q000187:drug effects; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012844:Sincalide / Q000494:pharmacology
chemical_list: D010446:Peptide Fragments; C410885:cholecystokinin 8; D002766:Cholecystokinin; D012844:Sincalide
keywords: Celiac artery; Cholecystokinin; Cranial mesenteric artery; Intermeal interval; Meal size