EFFECT OF CLOZAPINE TREATMENT ON SEROTONIN-2-RECEPTOR BINDING IN THE BLOOD-PLATELETS OF SCHIZOPHRENIC-PATIENTS

The effect of clozapine and typical neuroleptic drug treatment on platelet serotonin(2) (5-HT2) binding kinetic constants (K-d, B-max) was studied in schizophrenic patients. Both treatments increased B-max by a comparable amount, indicating increased: numbers of 5-HT2 sites, although not all typical neuroleptic drugs were effective in this regard. Clozapine, but not typical neuroleptic drugs, increased K-d, indicating a lower affinity of the 5-HT2 sites for 5-HT. In a multiple regression model, low B-max at baseline predicted poor outcome on Brief Psychiatric Rating Scale measures in the clozapine-treated patients but not the neuroleptic-treated patients.