Blockade of delta-opioid receptors in the nucleus accumbens prevents ethanol-induced stimulation of dopamine release.
Naltrindole, a specific delta-opioid antagonist, infused by reverse dialysis in the nucleus accumbens of freely moving rats completely prevented the increase in extracellular dopamine concentrations elicited in the nucleus accumbens by ethanol (1.0 g/kg i.p.) as well as by the delta-opioid receptor agonist [D-Ala2]deltorphin II (50 microM), also perfused by reverse dialysis, but not by cocaine (15 mg/kg s.c.). The results provide in vivo evidence for a critical role of delta-opioid receptors in the dopamine-releasing properties of ethanol in vivo.
Department of Toxicology, University of Cagliari, Italy.
E
E
Acquas
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M
Meloni
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Di Chiara
D000818:Animals; D003042:Cocaine / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D000431:Ethanol / Q000037:antagonists & inhibitors*; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D009019:Morphinans / Q000494:pharmacology*; D009271:Naltrexone / Q000031:analogs & derivatives*; D009292:Narcotic Antagonists / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017465:Receptors, Opioid, delta / Q000037:antagonists & inhibitors* / Q000502:physiology
D007211:Indoles; D009019:Morphinans; D009292:Narcotic Antagonists; D009842:Oligopeptides; D017465:Receptors, Opioid, delta; C060209:deltorphin II, Ala(2)-; D000431:Ethanol; D009271:Naltrexone; C055382:naltrindole; D003042:Cocaine; D004298:Dopamine