Acquisition and reinstatement of MDMA-induced conditioned place preference in mice pre-treated with MDMA or cocaine during adolescence.
Those who take ecstasy are more likely to consume other drugs than non-users with cocaine abuse being reported by 75.5% of high school student MDMA (+/- 3,4-methylenedioxymetamphetamine hydrochloride) users. The aim of this work was to evaluate the effects of exposure during adolescence to MDMA, cocaine or to both drugs on the MDMA-induced conditioned place preference (CPP) in adult mice. Animals received two daily administrations of saline, 10 mg/kg of MDMA, 25 mg/kg of cocaine or 10 mg/kg of MDMA plus 25 mg/kg of cocaine over 3 days (from PD28 to 30). Three weeks after pre-treatment, the MDMA-induced CPP procedure was initiated (PD52). Acquisition of CPP was induced with a sub-threshold dose of MDMA (1.25 mg/kg) only in animals treated during adolescence with MDMA alone. Preference was established in all the groups after conditioning with 10 mg/kg of MDMA, while the time required to achieve extinction was longer in those pre-treated with cocaine or MDMA alone (46 and 28 sessions, respectively). Moreover, preference was reinstated with progressively lower priming doses of MDMA in mice pre-treated with MDMA or cocaine alone. These results demonstrate that early exposure to MDMA or cocaine induces long-lasting changes that last until adulthood and modify the response of animals to MDMA.
Daza-Losada
Manuel
M
Unidad de Investigación Psicobiología de las Drogodependencias, Departamento de Psicobiología, Facultad de Psicología, Universitat de Valencia, Spain.
Rodríguez-Arias
Marta
M
Aguilar
María A
MA
Miñarro
José
J
D000367:Age Factors; D000818:Animals; D002755:Choice Behavior / Q000187:drug effects*; D003042:Cocaine / Q000494:pharmacology*; D003213:Conditioning, Psychological / Q000187:drug effects*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006213:Hallucinogens / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051379:Mice; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000008:administration & dosage / Q000494:pharmacology*
D006213:Hallucinogens; D003042:Cocaine; D018817:N-Methyl-3,4-methylenedioxyamphetamine