Alterations in opiate receptor function after chronic ethanol exposure.
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curve for morphine-induced stimulation of striatal dopamine metabolism was shifted to the right in mice which had been withdrawn for 24 hours after chronic consumption of an ethanol-containing liquid diet.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.
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000437:Alcoholism / Q000378:metabolism*; D000818:Animals; D002421:Caudate Nucleus / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D004090:Dihydromorphine / Q000494:pharmacology; D004295:Dihydroxyphenylalanine / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009020:Morphine / Q000494:pharmacology; D011957:Receptors, Opioid / Q000187:drug effects*
D011957:Receptors, Opioid; D015102:3,4-Dihydroxyphenylacetic Acid; D004295:Dihydroxyphenylalanine; D009020:Morphine; D004090:Dihydromorphine; D004298:Dopamine