Central administration of glp-1 (7-36)amide inhibits food and water intake in rats. Tang-Christensen, Mads, Philip J. Larsen, R[umlaut]udiger G[diaeresis]oke, Anders Fink-Jensen, David S. Jessop, Morten M[stod]oller, and S[stod]oren P. Sheikh. Laboratory of Clinical Pharmacology, Dept. of Clinical Biochemistry 7642, State University Hospital of Copenhagen, Department of Medical Anatomy Section-B, The Panum Institute, University of Copenhagen, NOVO-NORDISK a/s, M[angstrom]al[stod]ov, and Department of Medicine, Bristol Royal Infirmary, University of Bristol, England
APStracts 3:0134R, 1996.
Glucagon-like-peptide-1(7-36)amide (GLP-1) and its pancreatic receptors are important for control of blood glucose levels. However, rat GLP-1 receptors are also localized in the brain, in hypothalamus, and in areas without a blood-brain barrier. When rats were kept on a food restriction schedule, intracerebroventricular (icv) injection of GLP-1 just before offering food, inhibited food intake. However, peripheral GLP-1 administration by intraperitoneal injection (ip) had little effect. GLP-1 effects on water intake and output were also investigated. Icv GLP-1 profoundly inhibited angiotensin II (AngII) induced drinking behaviour in rats, and water intake was suppressed by exogenous GLP-1 in rats habituated to a water restriction schedule. These effects were reproduced by ip administration of GLP -1. Furthermore, icv GLP-1 stimulated urinary excretion of water and sodium. The centrally elicited effects were blocked by the GLP-1 antagonist exendin(9-39)amide, whereas the N-terminally extended and inactive GLP-1(1-36)amide had no effect upon feeding and drinking. GLP-1 had no effect in behavioural assays measuring exploratory locomotor activity and conditioned taste aversion. In conclusion, GLP-1 may play a physiological role in regulation of both ingestion and the water and salt homeostasis.

Received 14 December 1995; accepted in final form 25 March 1996.
APS Manuscript Number R791-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 16 April 96