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PubMed · 6283066

Alterations in opiate receptor function after chronic ethanol exposure.

P L Hoffman·S Urwyler·B Tabakoff
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Abstract

The dose-response curve for morphine-induced stimulation of striatal dopamine metabolism was shifted to the right in mice which had been withdrawn for 24 hours after chronic consumption of an ethanol-containing liquid diet. The apparent ED50 for morphine was increased by 33% in ethanol-treated mice. Concomitant with the shift in the dose-response curve, the affinity for dihydromorphine of the high-affinity caudate morphine receptor was decreased in ethanol-treated mice. The change in receptor properties after ethanol treatment included a decreased sensitivity of the receptor to the effects of sodium ion on morphine binding. The results suggest: 1) that the effect of morphine on dopamine metabolism in the mouse striatum is, at least in part, mediated by receptors that exhibit a high affinity for dihydromorphine: and 2) that ethanol treatment and withdrawal may induce specific changes in these particular opiate receptors.

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3,4-Dihydroxyphenylacetic AcidAlcoholismAnimalsCaudate NucleusCorpus StriatumDihydromorphineDihydroxyphenylalanineDopamineHumansMaleMiceMice, Inbred C57BLMorphineReceptors, OpioidJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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P L Hoffman, S Urwyler, B Tabakoff. 1982. Alterations in opiate receptor function after chronic ethanol exposure.. https://pubmed.ncbi.nlm.nih.gov/6283066/

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