QUANTITATIVE AUTORADIOGRAPHY OF DOPAMINE-D1 RECEPTORS, D2 RECEPTORS, AND DOPAMINE UPTAKE SITES IN POSTMORTEM STRIATAL SPECIMENS FROM SCHIZOPHRENIC-PATIENTS

A number of previously published homogenate receptor binding studies h ave postulated that dopaminergic dysfunction in schizophrenia may be r elated to abnormalities in dopamine receptors, In this study, postmort em striatal specimens from patients with schizophrenia, normal control s, and psychiatric controls that had received neuroleptics were studie d with quantitative autoradiography for dopamine receptors, Autoradiog raphy with single concentrations of [H-3] - SCH 23390 for D1 receptors , [H-3] - raclopride for D2 receptors, and [H-3] - CFT for dopamine up take sites failed to define significant differences between the study groups, [H-3] - CFT bound in a patchy distribution in the striatum tha t is believed to correspond to striosomal and matrix striatal compartm ents. There were no differences between groups when [H-3] - CFT bindin g density was examined in the striosomal and matrix compartments. Ther e were also no differences between groups in the percentage of striata l area occupied by striosomal or matrix compartments as defined by [H- 3] - CFT binding, We conclude that abnormalities of these dopamine rec eptor subtypes are probably not primary features of the schizophrenic syndrome in the brain collection examined, Previous reports of elevate d D2 receptor binding in schizophrenia may have been related to drug t reatment effects, Alternatively, the relatively high affinity of ligan ds used in previous studies for D4 receptors may explain the discrepan cy in our findings, Unchanged [H-3] - CFT binding in the schizophrenic group also suggests that the density of mesostriatal neurornal termin als is not altered in schizophrenia,