REORGANIZATION OF THE ULTRASTRUCTURE OF NEOCORTICAL NEURONS IN RATS TREATED WITH CELL-FREE DNA

Abstract

Neuron ultrastructure was studied in layers III-V of rat brain neocortex 24 hours after intraperitoneal (n=3) or intravenous (n=3) injection of cell-free DNA (7.7×10 -5 g/kg body weight). A plastic restructuring of nuclear chromatin, nucleolar hypertrophy, deep invaginations of nuclear envelope, hyperplasia of mitochondria and their close contact with other organelles and the nucleus, formation of cytoplasmic tubulovesicular bodies which may promote enhanced synaptic vesicle transport to presynaptic axonal terminals, activation of astrocyte glia were found. The data obtained suggest that injection of cell-free DNA lead to pronounced ultrastructural reorganization in neocortical neurons directed to protein synthesis activation, enhancement of synaptic transmission efficiency, as well as intensification of energy metabolism, that may contribute to reparative and compensatory restorative processes in cerebral ischemic pathology.

Keywords

cerebral cortex / neurons / ultrastructure / plasticity / extracellular DNA

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