Reduction in striatal 5-hydroxytryptamine turnover following chronic administration of ethanol to rats

Male Sprague-Dawley rats were given 10% (v/v) ethanol to drink for 28 days and the effects of the drug on the brain 5-hydroxytryptamine (5-HT) turnover were studied. Turnover was decreased in the corpus striatum after ethanol treatment due to a decrease in 5-hydroxyindol-3-ylacetic acid (5-HIAA), and an increase in 5-HT, concentration. Noradrenaline concentration was also increased in this region, but those of dopamine and GABA were similar to control values. Ethanol had no effect on any of the neurotransmitters studied in the brain stem and hippocampus, nor on the activity of monoamine oxidase type A (MAO-A) and 5-HT uptake in the three brain regions. Chronic ethanol administration caused a selective decrease in striatal 5-HT turnover which was unrelated to either its rate of inactivation, or the activity of other brain neurotransmitters. These findings are discussed in relation to those obtained in previous studies.