STRUCTURAL CHARACTERISTICS AND SPATIAL ORGANIZATION OF THE PARVALBUMIN-CONTAINING NEURONS OF THE SOMATOSENSORY AREA OF THE SI CEREBRAL CORTEX IN RATS

Abstract

The aim of the study was laminar morphometric study of immuno-labeled parvalbumin containing (PA+) neurons of cortical somatosensory area SI in outbred albino rats (n=10). The study of frontal and tangential sections 60 μm and 4 μm thick demonstrated a considerable diversity in cell body shape and size as well as in branching of the processes in PA+neurons in all the layers of the cortex. The greatest number of PA+neurons (47.1%) was found in layer IV of the cortex, in the zone of barrel formation. The study of tangential sections has shown that the largest number of PA+neurons was localized in the barrel septa (43%). In layer IV, their greatest density was detected in the walls of the barrel, making it possible to clearly identify their outlines. Quantitative predominance of PA+neurons in the septa may be associated with the direction of their dendrite course into the inner part of the barrel and the formation of dendro-dendritic gap junctions that, in turn, could be a morphological basis of individual local pacemaker rhythmogenesis and regulation of the functional state of the cortical columns

Keywords

cerebral cortex / barrels / neurons / parvalbumin / immunohistochemistry

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