title: A glucagon-like peptide-1 receptor agonist and an antagonist modify macronutrient selection by rats.
abstract: The hypothesis that peripheral glucagon-like peptide-1 (GLP-1) is a regulator of both food intake and macronutrient selection in rats was tested by administration of its antagonist, exendin 9-39, and its agonist, exendin 4. The effect of exendin 9-39 given intraperitoneally (i.p.) on food intake was measured after carbohydrate, protein or fat preloads, and on choice between a protein-free, high carbohydrate (CHO) diet and a high protein, low carbohydrate (PRO) diet. The effect of exendin 4 on selection between the CHO and PRO diets was also investigated. Exendin 9-39 significantly enhanced food intake suppression occurring after glucose, but not after corn oil or albumin preloads. In diet selection studies, exendin 9-39 selectively decreased intake of only the CHO diet. In contrast, exendin 4 decreased intake of only the PRO diet. Thus, we suggest that peripheral GLP-1 plays a role in the regulation of macronutrient selection as well as food intake in rats.
authors.affiliation: Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Canada M5S 3E2.
authors.forename: C T
authors.initials: CT
authors.lastname: Peters
authors.forename: Y H
authors.initials: YH
authors.lastname: Choi
authors.forename: P L
authors.initials: PL
authors.lastname: Brubaker
authors.forename: G H
authors.initials: GH
authors.lastname: Anderson
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects* / Q000502:physiology; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake / Q000187:drug effects*; D000077270:Exenatide; D005934:Glucagon; D000067757:Glucagon-Like Peptide-1 Receptor; D007274:Injections, Intraperitoneal; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D018027:Receptors, Glucagon / Q000819:agonists* / Q000037:antagonists & inhibitors* / Q000502:physiology; D013997:Time Factors; D014688:Venoms
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; C000593835:Glp1r protein, rat; D000067757:Glucagon-Like Peptide-1 Receptor; D010446:Peptide Fragments; D010455:Peptides; D018027:Receptors, Glucagon; D014688:Venoms; C083773:exendin (9-39); D005934:Glucagon; D000077270:Exenatide