The authors found that platelet serotonin concentrations were
significantly elevated in patients with chronic schizophrenia and in
patients with bipolar major depressive disorder. High-affinity serotonin
uptake was significantly reduced only in patients with bipolar major
depressive disorder. Thrombin-induced release of serotonin from platelets
in any patient group was not different from that of normal control
subjects. Platelet serotonin storage in chronic schizophrenic patients was
also not different from that in normal control subjects. These platelet
findings could not be explained by age, sex, or medication variables. The
authors suggest that the pharmacodynamics of platelet serotonin may be
different in chronic schizophrenia than in bipolar major depressive
disorder.Abstract Teaser