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PubMed · 1786525

Chronic opiate agonists down-regulate prodynorphin gene expression in rat brain.

P Romualdi·G Lesa·S Ferri
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Abstract

The effects of long-term administration of opioid agonists on the regulation of prodynorphin gene expression in rat brain were investigated. Chronic intracerebroventricular treatment with the synthetic opioid agonist acting on the kappa receptor, U-50,488H, and the classic mu agonist morphine markedly decreased prodynorphin mRNA levels in hypothalamus, hippocampus and striatum of tolerant rats. Levels of ir-Dynorphin A remained unchanged except in two cases. Chronic exposure to opiates thus appears to induce modifications of the endogenous opioid system, as regards gene expression regulation.

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3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-IsomerAnalgesicsAnimalsBlotting, NorthernBrain ChemistryCorpus StriatumDNA ProbesDown-RegulationEnkephalinsGene Expression RegulationHippocampusHypothalamusMaleMorphineNarcoticsProtein PrecursorsPyrrolidinesRNA, MessengerRatsRats, Inbred StrainsJournal ArticleResearch Support, Non-U.S. Gov't

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P Romualdi, G Lesa, S Ferri. 1991-11-01. Chronic opiate agonists down-regulate prodynorphin gene expression in rat brain.. https://doi.org/10.1016/0006-8993(91)91525-6

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