CORRELATIONS BETWEEN STRUCTURAL ORGANIZATION PARAMETERS OF THE SOMATOSENSORY CORTEX AND SPATIAL LEARNING CAPABILITIES IN RATS RESPECTING DOPAMINERGIC TRANSMISSION DIFFERENCES

The results of a recent study of the bioelectrical activity of the somatosensory cortex of the rat brain indicate the involvement of this structure in spatial orientation processes. The authors showed that the nature of the bioelectrical activity can change depending on the point in space where the animal is located. At the same time, the area of the primary somatosensory cortex, which contains the representations of the whiskers - the barrel cortex - remained unexplored. Previously, we conducted studies of the ability of rats to spatial learning, and then studied the structural organization of the brain in some of these animals. Thus, the goal of this work is to search for possible correlations between the parameters characterizing the behavior of rats during spatial learning and the data obtained in histomorphological studies of the somatosensory cortex of these rats. The object of the study is the data obtained as a result of testing in an eight-arm radial maze and in morphometric studies of the somatosensory cortex of the Wistar and DATHET rats. Based on the results of the analysis, we made the assumption that success in spatial learning is directly related to the number of neurons in layer 4. In layer 5, this role is assigned primarily to glia. The differences between the groups of animals here are quantitative. Qualitative differences were observed in relation to layers 2/3 and 6. Thus, Wistar rats are characterized by direct correlations of behavioral indicators with the number of neurons in the first of the above layers, and in layer 6 - with the density of glia distribution. At the same time, such correlations are absent in DAT-HET rats

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