title: Disulfiram stimulates dopamine release from noradrenergic terminals and potentiates cocaine-induced dopamine release in the prefrontal cortex.
abstract: BACKGROUND
  Disulfiram efficacy in treatment of cocaine addiction is attributed to the inhibition of dopamine-β-hydroxylase and reduction in brain noradrenaline (NA)/dopamine (DA) ratio.
  
  
  OBJECTIVE
  Using microdialysis, we investigated if disulfiram causes DA release from noradrenergic terminals and modifies cocaine-induced DA release.
  
  
  RESULTS
  Disulfiram reduced extracellular NA in the medial prefrontal (mPF) cortex, occipital cortex, accumbens and caudate nuclei, while it markedly increased DA not only in mPF but also in the occipital cortex, despite its scanty dopaminergic afferences, and modestly increased DA in the accumbens and caudate nuclei, despite their dense dopaminergic innervation. Disulfiram-induced DA accumulation was reversed in both cortices by tetrodotoxin infusion and by systemic administration of the α(2)-adrenoceptor agonist clonidine, but was not modified by the α(2)-adrenoceptor antagonist RS 79948 or the D(2)-like agonist quinpirole. Disulfiram prevented cocaine-induced NA release in the mPF cortex and nucleus accumbens, potentiated cocaine-induced DA release in the mPF cortex but failed to modify cocaine effect in the nucleus accumbens. DA release induced by disulfiram-cocaine combination in the mPF cortex was prevented by clonidine but not by quinpirole.
  
  
  CONCLUSIONS
  We suggested that disulfiram, by removing NA-mediated inhibitory control on noradrenergic terminals, causes an unrestrained cocaine-induced DA release from those terminals in the mPF cortex. In the accumbens and caudate nuclei, "allogenic" DA concentration might be clouded by DA originated from dopaminergic terminals. The possible role of "allogenic" DA in disulfiram ability to prevent stress-induced reinstatement of cocaine seeking is discussed.
authors.affiliation: Department of Neuroscience, University of Cagliari, Monserrato, Italy. pdevoto@unica.it
authors.forename: Paola
authors.initials: P
authors.lastname: Devoto
authors.forename: Giovanna
authors.initials: G
authors.lastname: Flore
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Saba
authors.forename: Roberto
authors.initials: R
authors.lastname: Cadeddu
authors.forename: Gian Luigi
authors.initials: GL
authors.lastname: Gessa
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D003042:Cocaine / Q000494:pharmacology*; D019970:Cocaine-Related Disorders / Q000188:drug therapy / Q000503:physiopathology; D004221:Disulfiram / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism*; D004299:Dopamine beta-Hydroxylase / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D017551:Microdialysis; D009638:Norepinephrine / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004791:Enzyme Inhibitors; D004299:Dopamine beta-Hydroxylase; D003042:Cocaine; D004221:Disulfiram; D004298:Dopamine; D009638:Norepinephrine