Repeated administration of 3,4-methylenedioxymethamphetamine augments cocaine's action on dopamine in the nucleus accumbens: a microdialysis study.
In this study, we examined the ability of a single injection of cocaine (20 mg/kg, i.p.) to augment extracellular dopamine levels in the nucleus accumbens two weeks after pretreating rats with either saline (1 ml/kg, i.p.) or the serotonin neurotoxin 3,4-methylenedioxymethamphetamine (20 mg/kg, s.c., twice daily for 4 days). The level of dopamine in the nucleus accumbens was measured using in vivo microdialysis. Cocaine produced a 400% increase in extracellular nucleus accumbens dopamine levels in control rats, whereas in 3,4-methylenedioxymethamphetamine treated rats the increase produced by cocaine was 800%, which was significantly different from controls. This suggests that 3,4-methylenedioxymethamphetamine, a relatively common drug of abuse, may alter subsequent vulnerability to cocaine dependence and abuse.
Morgan
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AE
Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
Horan
B
B
Dewey
S L
SL
Ashby
C R
CR
D000818:Animals; D003042:Cocaine / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D004357:Drug Synergism; D008297:Male; D017551:Microdialysis; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000008:administration & dosage*; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018490:Serotonin Agents / Q000008:administration & dosage*; D019966:Substance-Related Disorders / Q000209:etiology
D018765:Dopamine Uptake Inhibitors; D018490:Serotonin Agents; D003042:Cocaine; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D004298:Dopamine