Platelet serotonin uptake in men with family histories of alcoholism.

Platelet serotonin uptake kinetics were examined in a carefully screened group of 28 male subjects, half of whom had an alcoholic father. Paired subjects were matched for a variety of characteristics, including age, race, sex, substance use history, height/weight ratio, season, and time of day for platelet serotonin uptake assays. The family history positive group had a significantly (p = 0.01) higher mean Vmax for platelet serotonin uptake (64.1 +/- 19, SD) compared to the control group without family histories of first-degree relatives with alcoholism (53.8 +/- 19). No significant differences in the affinity constant (Km) or in the Hill constant were found between groups. The results are consistent with the possibility that a higher Vmax of platelet serotonin uptake indicates a biologic factor associated with alcoholism risk.