REACTIVE CHANGES OF THE RAT BRAIN CELL ELEMENTS DUE TO CIRCULATORY HYPOXIA

The research is devoted to establishment of a complex of the main structural, spatial and quantitative reactive changes of cellular elements of anterior cingulate cortex and the midbrain paranigral nucleus located in different conditions of forbrain circulator hypoxia. The data obtained will help to present differences in reactivity of the brain cells in relationship with each other and with a wall of a blood capillary, and also can be used as a basis for modeling pharmacological correction of posthypoxic conditions. Histologic sections of forward medial part of the paranigral nucleus and layers of the V-VI pregenual cingular field of adult rats in 7 days after occlusion of both general carotids were examined. The sections of intact animals and sham-operated animals were studied too. In the sections, stained after Nissl, the ratio of the low-changed, hypochromic, picnomorphic and shadow neurons, quantity of astrocytes, oligodendrocytes, microgliocytes and endotheliocytes, the viable low-changed and hypochromic neurons, astrocytes and microgliocytes cell bodies area, length of astrocytes axial shoots, distance from bodies of viable neurons and astrocytes to a wall of capillaries, the gliocyte-neuronal index were determined by methods of identification of glial fibrillar acid protein and Iba1-protein. The cellular elements of the surviving brain in different conditions of circulator hypoxia were established to characterize by a range of the expressed pathological changes. Neurons were in process of picnotization, lysis and transformation into shadow cells. Cells of the nuclear zone of hypoxia trended to death or picnosis. The neurons located outside the hypoxic area and being affected by only humoral influence of the glutamate-calcium cascade, were inclined to sharp swelling. Microgliocyte reaction in the form of poorly expressed increase in their number and structural signs of activation was an early diffusion manifestation of the forbrain focal hypoxia. Endotheliocytes proliferation in terms of early ischemic influence did not connect with a cascade reactions chain and was observed only in hypoxia focus. The concentration of viable neurons and astrocytes near blood capillaries, and also the increase of number of satellite glial forms were adaptation mechanism and condition for survival of cells under various conditions of ischemic influence on the brain.

neurons, astrocytes, gliocytes, endotheliocytes, hypoxia, reactive changes