title: Drug-induced reinstatement to heroin and cocaine seeking: a rodent model of relapse in polydrug use.
abstract: The authors investigated several features of polydrug use in rats. Heroin and cocaine were self-administered following responses on different levers, with only 1 drug and 1 lever available on alternate days of training. Four doses of each drug (heroin: 25, 50, 100, and 200 microg/kg/infusion; cocaine: 0.25, 0.5, 1, and 2 mg/kg/infusion) were tested, and each rat was exposed to a single dose combination. Rats readily developed drug-specific and dose-related responding. During extinction, rats displayed a significant bias for responding on the cocaine- associated lever. Priming injections of either cocaine (20 mg/kg) or heroin (0.25 mg/kg) reinstated responding that was selective for the lever previously associated with each drug. These results suggest that in this type of polydrug use, drugs have the capacity to activate drug-seeking behavior selectively oriented toward stimuli previously associated with their administration.
authors.affiliation: Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, Quebec, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Leri
authors.forename: J
authors.initials: J
authors.lastname: Stewart
mesh_terms: D000818:Animals; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology; D019970:Cocaine-Related Disorders / Q000523:psychology*; D003216:Conditioning, Operant / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005108:Extinction, Psychological; D003932:Heroin / Q000008:administration & dosage / Q000494:pharmacology; D006556:Heroin Dependence / Q000523:psychology*; D007262:Infusions, Intravenous; D008297:Male; D009294:Narcotics / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D020318:Rats, Long-Evans; D012008:Recurrence; D012646:Self Administration
chemical_list: D009294:Narcotics; D003932:Heroin; D003042:Cocaine