3H-spiperone binding in platelet membranes: a possible biological marker for schizophrenia

High-affinity-specific 3H-spiperone binding to platelet membranes was carried out in 30 schizophrenic patients, without prior antipsychotic medication, fulfilling the Research Diagnostic Criteria, and in 30 matched control subjects. The psychosis was rated on the Modified Brief Psychiatric Rating Scale. Compared with healthy subjects, schizophrenic patients had significantly higher 3H-spiperone binding due to a lower dissociation constant (38%), i.e. increased affinity. No significant difference was observed in the maximum number of binding sites (Bmax) between the two groups. It is our contention that 3H-spiperone binding to platelets may be a biological marker for schizophrenia.