title: Food deprivation-like effects of neuropeptide Y on heroin self-administration and reinstatement of heroin seeking in rats.
abstract: Numerous findings suggest that drug seeking and ingestive behaviors share common neurobiological mechanisms, but the relevant pathways are unknown. Dietary manipulations result in changes in endocrine the and/or neuropeptide signals, such as the hormones leptin and ghrelin, which are dynamically linked to energy balance and the regulation of feeding behavior. We have recently demonstrated that food deprivation-induced reinstatement of heroin seeking can be blocked with leptin, and others have suggested a role for ghrelin in drug-related behaviors. The feeding-relevant effects of leptin and ghrelin involve the inhibition or activation, respectively, of neuropeptide Y/agouti-related peptide (NPY/AGRP) neurons in the hypothalamus. However, the effects of NPY, a highly potent orexigenic peptide, on drug-related behaviors have not been thoroughly studied. Here we examined the effect of acute NPY administration on the rate of heroin self-administration and the reinstatement of extinguished heroin-seeking behavior. Heroin intake (0.05mg/kg/infusion) was tested using a self-administration procedure (FR-1), 10-min post-NPY injections (0.0, 4.0, and 10microg/rat, ICV). In a different group of rats, NPY-induced reinstatement (0.0, 4.0, and 10microg/rat, ICV) of extinguished heroin seeking was assessed. NPY injections increased on-going heroin self-administration, and induced a reinstatement of extinguished heroin-seeking behavior. These findings suggest that NPY can modulate the rewarding and conditioned reinforcing effects of drugs of abuse.
authors.affiliation: Department of Psychology, Center for Studies in Behavioral Neurobiology, Concordia University, 7141 Sherbrooke Street West, H4B 1R6, Montreal, Quebec Canada.
authors.forename: Tia
authors.initials: T
authors.lastname: Maric
authors.forename: Stephanie
authors.initials: S
authors.lastname: Tobin
authors.forename: Tammie
authors.initials: T
authors.lastname: Quinn
authors.forename: Uri
authors.initials: U
authors.lastname: Shalev
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003216:Conditioning, Operant / Q000187:drug effects; D004195:Disease Models, Animal; D005508:Food Deprivation; D003932:Heroin / Q000008:administration & dosage*; D006556:Heroin Dependence / Q000523:psychology*; D008297:Male; D009294:Narcotics / Q000008:administration & dosage*; D009478:Neuropeptide Y / Q000494:pharmacology*; D051381:Rats; D020318:Rats, Long-Evans; D012055:Reinforcement Schedule; D012054:Reinforcement, Psychology; D012646:Self Administration
chemical_list: D009294:Narcotics; D009478:Neuropeptide Y; D003932:Heroin