Cocaine-induced conditioned place preference in mice: induction, extinction and reinstatement by related psychostimulants.
Reinstatement of drug-seeking behavior in animals is relevant to drug relapse in humans. In the present study, we employed the conditioned place preference (CPP) paradigm to investigate the extinction and reinstatement of the place-conditioned response, a model that is consistent with drug-seeking behavior. Cocaine-induced CPP was rendered in Swiss Webster mice and then extinguished after repeated saline injections (8 days) in both the previously cocaine-paired compartment and the saline-paired compartment. Following the extinction phase, the reinstatement of CPP was investigated. Cocaine-experienced mice were challenged with one of the following psychostimulants, cocaine (15 mg/kg), methamphetamine (METH; 0.5 mg/kg), methylphenidate (MPD; 20 mg/kg) and phencyclidine (PCP; 5 mg/kg). The priming injection of cocaine, METH and MPD, unlike PCP, induced a marked preference for the previously cocaine-paired compartment. This finding suggests that all three psychostimulants reinstated the CPP response, and METH and MPD substituted for the reinforcing cue of cocaine. A challenge injection of cocaine administered two and four weeks after the reinstatement of CPP indicated that CPP was maintained up to two weeks. The finding that METH and MPD but not PCP reinstated and supported cocaine-induced CPP suggests that the CPP paradigm may be a useful tool for drug discrimination studies and the reinstatement of drug-seeking behavior.
Itzhak
Yossef
Y
Department of Psychiatry and Behavioral Sciences, R-629, Gautier Building Room # 503, 1011 NW 15th Street, University of Miami School of Medicine, Miami, FL 33136, USA. yitzhak@med.miami.edu
Martin
Julio L
JL
D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003042:Cocaine / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005108:Extinction, Psychological / Q000187:drug effects*; D008297:Male; D008694:Methamphetamine / Q000494:pharmacology; D008774:Methylphenidate / Q000494:pharmacology; D051379:Mice; D010622:Phencyclidine / Q000494:pharmacology
D000697:Central Nervous System Stimulants; D018765:Dopamine Uptake Inhibitors; D018691:Excitatory Amino Acid Antagonists; D008774:Methylphenidate; D008694:Methamphetamine; D003042:Cocaine; D010622:Phencyclidine