APPLICATION OF [H-3] L-N-G-NITRO-ARGININE LABELING TO MEASURE CEREBELLAR NITRIC-OXIDE SYNTHASE IN PATIENTS WITH SCHIZOPHRENIA

Brains from patients with schizophrenia have been reported to contain deficient and dysplastic forebrain neurons containing nitric oxide syn thase (NOS). As part of a study of NOS in schizophrenia, we decided to investigate the cerebellum, which has particularly high levels of NOS . We used an autoradiographic method to measure the density and distri bution of NOS. Sections of frozen cerebellum removed at autopsy were l abelled with the selective NOS inhibitor [H-3]L-N-G-nitro-arginine, NO S levels were visualized in sagittal sections of vermis from 16 contro l subjects and 21 schizophrenia patients, and measurements were taken from the three groups of developmentally-distinct lobules I-V, VI-VII and VIII-X. The highest NOS density was in the Purkinje/molecular laye r of cerebellar cortex, although there was some NOS in the granule cel l layer. There were no differences in Purkinje/molecular or granule ce ll layer NOS levels between the two groups of subjects. The mild struc tural faults in cerebellar vermis observed in some patients with schiz ophrenia probably do not involve reductions in NOS-containing cells.