Serotonin levels and platelet uptake during premenstrual tension.

Premenstrual tension was studied in 16 females, using both biochemical and psychological parameters during the pre- and postmenstrual phases. Uptake of serotonin (5-HT) and the levels of 5-HT in platelet-rich plasma and platelet-poor plasmas were determined. Degrees of distress experienced pre- and postmenstrually were quantified via the Moos menstrual distress questionnaire. The mean Vmax was significantly lower during the premenstrual (tension) phase (8.2 +/- 0.9 pmol/min) as compared to the postmenstrual (normal) phase (14.4 +/- 3.2 pmol/min). There was no significant difference in the Km values. A highly significant (p less than 0.001) reduction in the levels of 5-HT in platelet-rich plasma (-23.2%) and platelet-poor plasma (-19.1%) was found during the premenstrual phase. There were correlations between the kinetic parameters of 5-HT uptake and some of the Moos symptoms.