Ethanol withdrawal alters apomorphine-induced motility.

Acute administration of ethanol is accompanied by alterations in dopamine turnover and release, and chronic ethanol exposure is associated with changes in biochemical measures of dopamine receptor function. This paper presents data examining the effects of chronic ethanol exposure on behavioral responses to the dopamine receptor agonist apomorphine. Measurements of behavior were obtained through the use of an electronic motility monitor which permitted the quantification of movements in terms of their characteristic frequency components. Results are presented which indicate that apomorphine-induced movements with modal frequencies of 2 Hz and of 8-9 Hz are significantly increased during the 12 to 24 hr following ethanol withdrawal, suggesting an increase in the functional responsiveness of central dopaminergic systems.