[Changes in the ultrastructure of neuroglia in some regions of the rat brain in manganese chloride poisoning].

Ultrastructure of astrocytes, olygodendrocytes and microgliocytes of caudate nucleus, substantia nigra and frontoparietal area of the cortex were studied under the influence of the everyday peroral treatment with MnCl2.4H2O during 30 days. Experimental animals were divided into two groups. Animals from the first group received 20 mg/kg of MnCl2.4H2O while for animals from the second one the dose made 50 mg/kg. Animals were killed on days 30 and 120 of the experiment. It was demonstrated that chloride manganese intoxication influences the ultrastructure of all types neuroglial cells, the majority of both macro- and microgliocytes remaining in normal state. Cytotoxic effect of manganese ions on astrocytes manifests in mitochondria destruction, widening of canaliculi and endoplasmic net cisterns, glycogenic granules accumulation, which leads to reduction of oxidative processes level in the nervous tissue. Increased phagocytic activity of the astrocytes was displayed in conditions of relatively high doses of MnCl2.4H2O. Microgliocyte reaction was distinctly dose-dependent and was manifested through their phagocytary activity increase. Oligodendrocytes were most stable to chloride manganese influence.