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Information × Registration Number 0211U005114, 0100U000307 , R & D reports Title The study of compensative - adaptive mechanisms of the nevous system under the influence of extreme factors popup.stage_title Head Rodynskyj Alexandr Georgievich, Registration Date 17-02-2011 Organization Dniepropetrovsk State Medical Akademy popup.description2 Scientific work tackles scientific problem which lies in detecting the ways and disclosing mechanisms of development of principally new level of growth of the spinal cord (SC) excitability, hyperreflection - spinal superreflection (SS) - state in which amplitude of reflector discharges is near the threshold of action of the most excitative nerve fibers and studies regularities of SC functioning in these conditions. While researching mechanisms of SC functioning in conditions of a specially high excitability it was found out, that manipulations with afferent orfice of segment reflex arcs (denervation, axocurrent blockade, tetanization) or systemic action of humoral factors (blocker of potentially dependent kalium canals - 4-aminopiridine (4-AP) or L-thyroxin) characterize mechanisms which can form basis of reflectory activity increase of SS, but individually each of these factors provides growth of monosynaptic reflex responses of no more than by 250-300 %. Only combination of denervation with action of potentially dependent kalium canals - 4-AP allowed to create a state of specially high excitability of SC - superreflection (SR). In this case amplitude of monosynaptic reflector discharges of ventral root (MD VR) exceeded the same finding in the intact animals by 800-900% and reached the threshold of excitation of VR fibers. It was shown that in conditions of SR there originates another component of MD VR, which reflects excitation of fibers that are not involved in reflector discharge. Experimental studies showed that hypothyroidism and hyperthyroidism essentially changes behavioral activity of animals according to ontogenesis. The greatest disturbances of integrative activity of CNS at thyroid gland dysfunctions were marked in the juvenile rats. It was shown by behavioral and cognitive deficiency and also increasing level of nonsaturated fat acids in a cerebral cortex by 26-48 % (hyperthyroidism), of the general lipids content in a cerebral cortex and a hippocampus by 22-98 % and quantity of glial fibrous acidic protein (GFAP) in a thalamus and a brainstem by 29-104 % (hypothyroidism). Decreasing of emotional activity (in hypothyroid and hyperthyroid animals) and memory (in hypothyroid animals) was recorded in the young animals. Given effect is accompanied by essential abnormalities in fatty-acid spectrum of lipids in a cerebral cortex and hippocampus. In particular, content of linoleic and linolenic acids in a cerebral cortex was increased on 97%. The content of palmitic acid, stearic and heneicosanic acids in a cerebral cortex and hippocampus was decreased by 42-63% (p<0,05). Active reconfigurations of astroglia cytoskeleton as increasing of GFAP expression (hypothyroidism) or decreasing of its content (hyperthyroidism) in a cerebral cortex, brainstem, hippocampus and thalamus are evidence of activation of metabolism in neurons. The results of the investigations showed decreasing of motor and emotional activity and also mnestic function at hypothyroidism that is due to essential content shifts of fatty acids of lipids in a cerebral cortex and hippocampus and GFAP accumulation in a cerebral cortex and thalamus by 35%-38% in the old animals. Product Description popup.authors Бєлоконь Вікторія Миколаївна Гніненко Олександр Миколайович Гузь Валерія Анатоліївна Гузь Людмила Василівна Демченко Олена Михайлівна Демченко Тетяна Вікторівна Мозгунов Олександр Володимирович Неруш Петро Опанасович Родинський Олександр Георгійович popup.nrat_date 2020-04-02 Close