Dopamine metabolism and receptor function after acute and chronic ethanol.

Acute ethanol treatment in rats elicits a selective increase in dihydroxyphenylacetic acid (DOPAC) content in striatum. In contrast, striatal DOPAC concentration does not differ from normal values after chronic ethanol treatment. Chronic administration of ethanol however causes a selective increase of specific [3H]spiroperidol binding and met-enkephalin content in the striatum. Kinetic analysis of [3H]spiroperidol binding data shows that after chronic ethanol treatment there is a significant increase in the affinity constant rather than in the number of binding sites for the ligand. Our results support the hypothesis that dopaminergic mechanisms at both pre- and postsynaptic level may be involved in the mediation of some of the central effects observed after ethanol consumption.