Reduced Capillary Density in the Prefrontal Cortex in Schizophrenia

Abstract

Neuroimaging studies have shown that the core symptoms of schizophrenia are associated with local changes of cerebral blood flow, particularly in the frontal cortex. Previously we reported ultrastructural damage of capillaries in the upper layers of the prefrontal cortex, Brodmann’s area (BA) 10 and in the visual cortex, BA schizophrenia. An electron microscopic morphometric study was performed to estimate capillary area density (N cap/mm<SUP>2</SUP>) in two upper layers of the prefrontal and visual cortices in 26 cases of schizophrenia and 26 normal controls. Capillary area density was lower in the prefrontal cortex in the schizophrenia group (-24%, p < 0.001) and in the subgroup of schizophrenia with predominantly negative symptoms (n=12, -35%, p < 0.001) as compared to controls. Group and subgroup differences were absent in the visual cortex. Dysfunction of neocortical microvasculature in schizophrenia is related to region-specific capillary deficiency in the prefrontal cortex. These changes might contribute to the lowered blood flow, reduced glucose metabolic rates, resting hypofrontality and hypoactivation reported in the prefrontal cortex of patients with schizophrenia.