Autoradiography with [H-3]8-OH-DPAT reveals increases in 5-HT1A receptors in ventral prefrontal cortex in schizophrenia

We previously reported increased glutamatergic innervation in orbital frontal cortex in schizophrenia. In view of the evidence that one serotonin (5-HT) receptor, the 5-HT1A subtype, is associated with cortical glutamatergic neurons, we have used quantitative receptor autoradiography to measure the specific binding of the 5-HT1A receptor ligand [H-3]8-OH DPAT (2 nM) in sections of orbital frontal cortex taken from 18 control and 12 schizophrenic postmortem brains. Schizophrenic patients, as compared with controls, had increased 5-HT1A receptor binding in the three orbital frontal regions examined. These effects were pronounced in the male subgroup, and were most apparent in the outer cortical laminae. These data are consistent with the hypothesis that schizophrenia is associated with an abnormal glutamatergic afferent innervation of orbital frontal cortex.