Platelet serotonergic binding sites in alcohol-dependent patients

The serotonin (5-hydroxytryptamine, 5-HT) uptake sites assessed with both [H-3]imipramine and [H-3]paroxetine, and the 5-HT2A receptors were simultaneously measured in platelets from 24 male subjects meeting the American Psychiatric Association's DSM-IV criteria for alcohol dependence and admitted for inpatient detoxification. Blood samples from alcoholic patients were collected during acute alcohol intoxication (day 0), during withdrawal (day 1), and after 2 weeks of abstinence (day 14). All patients met the criteria for type II alcoholism. Alcohol misuse was found to be associated with an increased number and a lower affinity of [H-3]paroxetine binding in comparison to the control values. Abstinence from alcohol for 2 weeks (day 14) resulted in a decrease in the number of 5-HT uptake sites labelled with [H-3]paroxetine compared to normal values, together with a significant decrease in the number of 5-HT2A binding sites. The present data indicate that altered serotonergic function existing in alcoholic patients is a reversible phenomenon that normalizes after detoxification and withdrawal.