[Activity of platelet serotonin receptors of patients with endogenous depression before and after treatment with antidepressive agents].

Effective 5-HT concentration eliciting the half-maximal rate of platelet deformation (aggregation) in drug-free bipolar or unipolar depressed women was significantly (p less than 0.001) lower as compared with matched controls (0.13 +/- 0.04 microM and 0.532 +/- 0.1 microM, respectively). After 1-3 months of antidepressant treatment this value increased to 0.47 +/- 0.16 microM and was no longer different from control. Possible mechanisms controlling the activity of serotonin2 platelet receptors are discussed.