Intermittent morphine treatment causes long-term desensitization of functional dopamine D2 receptors in rat striatum

Autor: Nestby, P, Tjon, G H, Visser, D T, Drukarch, B, Leysen, J E, Mulder, A H, Schoffelmeer, A N
Přispěvatelé: Anatomy and neurosciences, Amsterdam Neuroscience - Neurodegeneration, CCA - Imaging, Radiology and nuclear medicine
Jazyk: angličtina
Rok vydání: 1995
Zdroj: Nestby, P, Tjon, G H, Visser, D T, Drukarch, B, Leysen, J E, Mulder, A H & Schoffelmeer, A N 1995, ' Intermittent morphine treatment causes long-term desensitization of functional dopamine D2 receptors in rat striatum ', European Journal of Pharmacology, vol. 294, no. 2-3, pp. 771-7 .
European Journal of Pharmacology, 294(2-3), 771-7. Elsevier
ISSN: 0014-2999
Popis: 3 weeks following cessation of intermittent morphine administration (10 mg/kg, s.c., once daily for 14 days), [3H]dopamine and [14C]acetylcholine release induced by 10 microM N-methyl-D-aspartate (NMDA) from superfused rat striatal slices appeared to be significantly higher than the release from striatal slices from saline-treated rats. A similar adaptive increase of the NMDA-evoked release of these neurotransmitters was observed in slices of the nucleus accumbens, whereas that of [3H]noradrenaline from hippocampal slices remained unchanged. Blockade of dopamine D2 receptors by 10 microM (--)-sulpiride enhanced NMDA-induced [3H]dopamine and [14C]acetylcholine release from striatal slices from saline-treated animals, but was found to be ineffective in this respect following intermittent morphine treatment. Moreover, morphine administration appeared to cause a profound decrease in the apparent affinity of the full dopamine D2 receptor agonist LY171555 (quinpirole) for these release-inhibitory dopamine D2 receptors, indicating the occurrence of dopamine D2 receptor desensitization. It is suggested that such a desensitization of dopamine D2 receptors on dopaminergic nerve terminals as well as on cholinergic interneurons may play a pivotal role in the long-lasting nature of behavioural sensitization upon cessation of treatment with morphine and possibly other drugs of abuse.
Databáze: OpenAIRE
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