title: Food intake in free-feeding and energy-deprived lean rats is mediated by the neuropeptide Y5 receptor.
abstract: The new neuropeptide Y (NPY) Y5 receptor antagonist CGP 71683A displayed high affinity for the cloned rat NPY Y5 subtype, but > 1, 000-fold lower affinity for the cloned rat NPY Y1, Y2, and Y4 subtypes. In LMTK cells transfected with the human NPY Y5 receptor, CGP 71683A was without intrinsic activity and antagonized NPY-induced Ca2+ transients. CGP 71683A was given intraperitoneally (dose range 1-100 mg/kg) to a series of animal models of high hypothalamic NPY levels. In lean satiated rats CGP 71683A significantly antagonized the increase in food intake induced by intracerebroventricular injection of NPY. In 24-h fasted and streptozotocin diabetic rats CGP 71683A dose-dependently inhibited food intake. During the dark phase, CGP 71683A dose-dependently inhibited food intake in free-feeding lean rats without affecting the normal pattern of food intake or inducing taste aversion. In free-feeding lean rats, intraperitoneal administration of CGP 71683A for 28 d inhibited food intake dose-dependently with a maximum reduction observed on days 3 and 4. Despite the return of food intake to control levels, body weight and the peripheral fat mass remained significantly reduced. The data demonstrate that the NPY Y5 receptor subtype plays a role in NPY-induced food intake, but also suggest that, with chronic blockade, counterregulatory mechanisms are induced to restore appetite.
authors.affiliation: Metabolic and Cardiovascular Diseases Research, Novartis Pharma AG, CH-4002 Basel, Switzerland. Leoluca.criscione@pharma,novartis.com
authors.forename: L
authors.initials: L
authors.lastname: Criscione
authors.forename: P
authors.initials: P
authors.lastname: Rigollier
authors.forename: C
authors.initials: C
authors.lastname: Batzl-Hartmann
authors.forename: H
authors.initials: H
authors.lastname: Rüeger
authors.forename: A
authors.initials: A
authors.lastname: Stricker-Krongrad
authors.forename: P
authors.initials: P
authors.lastname: Wyss
authors.forename: L
authors.initials: L
authors.lastname: Brunner
authors.forename: S
authors.initials: S
authors.lastname: Whitebread
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: C
authors.initials: C
authors.lastname: Gerald
authors.forename: R O
authors.initials: RO
authors.lastname: Heurich
authors.forename: M W
authors.initials: MW
authors.lastname: Walker
authors.forename: M
authors.initials: M
authors.lastname: Chiesi
authors.forename: W
authors.initials: W
authors.lastname: Schilling
authors.forename: K G
authors.initials: KG
authors.lastname: Hofbauer
authors.forename: N
authors.initials: N
authors.lastname: Levens
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000502:physiology*; D001667:Binding, Competitive; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D003213:Conditioning, Psychological / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D004326:Drinking / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism / Q000502:physiology; D007328:Insulin / Q000097:blood / Q000494:pharmacology; D008297:Male; D051379:Mice; D009281:Naphthalenes / Q000494:pharmacology*; D009478:Neuropeptide Y / Q000378:metabolism*; D011743:Pyrimidines / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017476:Receptors, Neuropeptide Y / Q000378:metabolism / Q000502:physiology*; D014280:Triglycerides / Q000097:blood
chemical_list: D001786:Blood Glucose; D007328:Insulin; D009281:Naphthalenes; D009478:Neuropeptide Y; D011743:Pyrimidines; D017476:Receptors, Neuropeptide Y; D014280:Triglycerides; C100568:neuropeptide Y5 receptor; C116786:CGP 71683 A; D002118:Calcium