Neuronal mechanisms regulating ethanol effects on the dopaminergic system.

Chronic ethanol consumption induces an increase in striatal 3H-Spiroperidol and 3H(-)Sulpiride specific binding by enhancing the affinity between the different dopaminergic recognition sites and the labelled ligands. Dopamine (DA) receptor supersensitivity is also suggested by the enhanced effect of neuroleptics in inducing hypomotility in rats treated with ethanol. The results, obtained by means of the administration of neuroleptics in comparison to ethanol treated rats, indicate a lack of cross tolerance between ethanol and other drugs acting on the dopaminergic recognition sites. These data suggest that ethanol effects on the dopaminergic system are mediated by events involving other neurotransmitter systems.