Periadolescent nicotine exposure causes heterologous sensitization to cocaine reinforcement.
There is increasing concern that abuse of tobacco during periadolescence increases the potential for later abuse of other drugs. To test this hypothesis, Sprague-Dawley rats received once-daily injections of either water or 0.4 mg/kg nicotine from postnatal day 35 through 44. Beginning on postnatal day 80, animals were tested in a 12-day cocaine-induced conditioned place preference (CPP) paradigm. Prior nicotine treatment enhanced the dose-response to cocaine. CPP training with 3.0 mg/kg i.p. cocaine increased time in drug-paired chambers by 50% in control rats and 94% in nicotine-exposed animals. Thus, periadolescent nicotine exposure produced long-term sensitization to an indirect-acting dopamine agonist.
McMillen
Brian A
BA
Department of Pharmacology and Toxicology, Brody School of Medicine at East Carolina University, Greenville, North Carolina 27834 USA. mcmillenb@mail.ecu.edu
Davis
Barbara J
BJ
Williams
Helen L
HL
Soderstrom
Ken
K
D000704:Analysis of Variance; D000818:Animals; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D013997:Time Factors
D009538:Nicotine; D003042:Cocaine