STRUCTURAL ORGANIZATION OF THE BARREL CEREBRAL CORTEX IN RAT (AN IMMUNOHISTOCHEMICAL STUDY)

Abstract

Immunohistochemical investigation of the regional distribution of neuronal and glial elements in the barrels of somatic cortex was carried out in rats (n=10). High level of synaptophysin protein expression was detected in the in barrel walls together with the accumulation of astroglial cells in their central areas. Ultrastructural investigation of chemical synapse structure showed the predominance of asymmetrical perforated axospinous contacts, presumably of excitatory type. The symmetric inhibitory synapses were more frequently located in the barrel walls in the areas of the denser neuronal perikarya distribution, as well as on the large dendritic processes. The number of vertically oriented myelinated axons within the barrels was found to be significantly greater than the number of the horizontally oriented interneuronal circuits.

Keywords

brain / barrel cortex / synapses / immunohistochemistry

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