[Decreased numerical density of pericapillary oligodendrocytes in the cortex in schizophrenia]

Autopsy samples from the prefrontal cortex were obtained from 22 schizophrenic cases and 22 normal controls. Capillaries and oligodendrocytes were viewed in paraffin sections stained with a Luxol-fast blue + cresyl violet. Electron microscopy was applied to study the ultrastructure of oligodendrocytes. Numerical density of pericapillary oligodendrocytes was measured in layer V of Broadmann's area 10. Subjects with schizophrenia had a significantly lower (-20,8%) numerical density of pericapillary oligodendrocytes compared to controls. The analysis for schizophrenic subgroups with predominantly positive or predominantly negative symptoms revealed a significant decrease in the numerical density of pericapillary oligodendrocytes only in the latter one (-29,4%). The numerical density of pericapillary oligodendrocytes in cases with predominantly positive symptoms also decreased (-8,3%) but not differed significantly from the controls. Electron microscopy revealed the prominent ultrastructural dystrophic and degenerative alterations of pericapillary oligodendrocytes in the prefrontal cortex in schizophrenic brains. The present study points out that the population of pericapillary oligodendrocytes is involved in the pathogenesis of schizophrenia. Damage and loss of pericapillary oligodendrocytes might lead to disruption of the blood-brain barrier and as a result to dysregulation of metabolic trafficking across the blood-brain barrier in the prefrontal cortex in schizophrenia.