Serotonin and alcohol: interrelationships.

Alcoholism is a multifaceted medicosocial problem. Recent literature discusses a common dyad, alcoholism and anxiety. Both disorders are interdigitated with the brain amine serotonin (5-hydroxytryptamine, 5-HT). Direct 5-HT activation reportedly attenuates alcohol consumption, whereas depletion enhances use patterns. Acute alcohol consumption has also been associated with a transient rise, albeit eventual diminished 5-HT turnover. A variety of 5-HT models have confirmed this observation, e.g., reduced platelet 5-HT content, uptake, and cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid. Such altered characteristics of 5-HT secondary to chronic alcohol use may explain the frequent morbidity of anxiety and/or depression. Acute alcohol consumption is also associated with accumulation of the 5-HT aldehyde derivative 5-hydroxymethtryptoline. Thus, alcohol may induce the in vivo formation of aldehydes, e.g., beta-carbolines, that themselves possess high lipophilicity and psychotropic activity. Future investigation into 5-HT-specific pharmacologic probes in alcoholism will be interesting. Preliminary research has consistently demonstrated that 5-HT-enhancing agents (e.g., zimelidine or fluvoxamine) decrease alcohol consumption, preference, and short-term memory decrements. Thus, 5-HT appears to represent at least one common denominator for a spectrum of behavioral disorders including anxiety and alcoholism.