title: Central administration of ghrelin preferentially enhances fat ingestion.
abstract: Ghrelin, a brain-gut peptide discovered from the stomach, stimulates growth hormone release, food intake, adiposity, and weight gain. Circulating ghrelin levels are modulated under conditions of positive and negative energy balance, however its effect on macronutrient selection is not known. The present experiment investigates the effect of ghrelin on single and two-diet feeding paradigms in high-carbohydrate (HC) and high-fat (HF) preferring rats. In the macronutrient selection test in which rats were given free access to either high-carbohydrate or high-fat diet, an intracerebroventricular (i.c.v.) administration of ghrelin potently enhanced fat intake over carbohydrate intake in both HC- and HF-preferring rats. In the diet preference test in which rats were given free access to both high-carbohydrate and high-fat diets simultaneously, an i.c.v. administration of ghrelin also preferentially enhanced fat consumption over carbohydrate in both HF- and HC-preferring rats. Intracerebroventricular administrations of galanin and neuropeptide Y enhanced fat and carbohydrate ingestion, respectively. Centrally administered ghrelin enhanced fat ingestion. These results provide further insights for the role of ghrelin in feeding behavior and the development of obesity.
authors.affiliation: Third Department of Internal Medicine, Miyazaki Medical College, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Shimbara
authors.forename: Muhtashan S
authors.initials: MS
authors.lastname: Mondal
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawagoe
authors.forename: Koji
authors.initials: K
authors.lastname: Toshinai
authors.forename: Shuichi
authors.initials: S
authors.lastname: Koda
authors.forename: Hideki
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Yukari
authors.initials: Y
authors.lastname: Date
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Nakazato
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004435:Eating / Q000187:drug effects*; D005223:Fats / Q000378:metabolism*; D005518:Food Preferences / Q000187:drug effects*; D019004:Galanin / Q000494:pharmacology; D054439:Ghrelin; D007276:Injections, Intraventricular / Q000379:methods; D008297:Male; D009478:Neuropeptide Y / Q000494:pharmacology; D036361:Peptide Hormones / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D005223:Fats; D054439:Ghrelin; D009478:Neuropeptide Y; D036361:Peptide Hormones; D019004:Galanin