title: Intravenous infusion of gastrin-releasing peptide-27 and bombesin in rats reveals differential effects on meal size and intermeal interval length.
abstract: We have previously shown that the intraperitoneal (i.p.) administration of gastrin-releasing peptide-27 (GRP-27) or bombesin (BN) (at 0.21, 0.41 and 1.03nmol/kg) reduces meal size (MS) and prolongs the intermeal interval (IMI). Here, we hypothesized that the intravenous (i.v.) administration of the same doses of GRP-27 and BN will be as effective as the i.p. administration in evoking these feeding responses. To test this hypothesis, we administered GRP-27 and BN i.v. and measured first MS (10% sucrose), IMI, satiety ratio (SR, IMI/MS) and second MS in overnight food-deprived but not water-deprived male Sprague Dawley rats. We found that (1) only GRP-27 reduced the first MS, (2) BN prolonged the IMI, (3) GRP-27 and BN increased the SR and (4) only BN reduced the size of the second meal. Contrary to our hypothesis, the i.v. administration of GRP-27 and BN affected the MS and IMI differently than did the i.p. administration. In conclusion, this pharmacological study suggests that the MS and IMI are regulated at different sites.
authors.affiliation: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States.
authors.forename: Martha C
authors.initials: MC
authors.lastname: Washington
authors.affiliation: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States.
authors.forename: Sarah
authors.initials: S
authors.lastname: Salyer
authors.affiliation: School of Medicine, Wayne State University, Detroit, MI 48202, United States.
authors.forename: Amnah H
authors.initials: AH
authors.lastname: Aglan
authors.affiliation: Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States. Electronic address: sayeghai@mytu.tuskegee.edu.
authors.forename: Ayman I
authors.initials: AI
authors.lastname: Sayegh
mesh_terms: D000818:Animals; D001066:Appetite; D001839:Bombesin / Q000008:administration & dosage / Q000502:physiology*; D002149:Energy Intake; D005247:Feeding Behavior; D019886:Gastrin-Releasing Peptide / Q000008:administration & dosage / Q000502:physiology*; D007262:Infusions, Intravenous; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012527:Satiation
chemical_list: D019886:Gastrin-Releasing Peptide; D001839:Bombesin
keywords: Bombesin; GRP; Gastrin-releasing peptide; Gastrointestinal tract; Intermeal interval; Meal size