Akimov O. Mechanisms of metabolic disorders in rat gastric mucosa under conditions of combined excessive intake of sodium nitrate and sodium fluoride and their correction by enterosorbents.

Thesis for a Doctor of Philosophy Degree in Specialty 222 “Medicine” (14.03.04 - Pathological Physiology). Ukrainian medical stomatological academy, Poltava, 2020. The thesis presents the theoretical generalization and solution of a scientific problem, which consists from establishment of molecular mechanisms of pathogenic action of nitrate ions and fluoride ions in the conditions of their combination on the gastric mucosa of rats and the experimental substantiation of its correction enterosorbents. The work was carried out on 90 white rats of both genders of the Wistar line weighting 185-240 g. Experimental, biochemical and mathematical-statistical methods of research were used. We established that the combined excessive intragastric intake of sodium nitrate (500 mg / kg) and sodium fluoride (10 mg / kg) for 30 days leads to dysregulatory changes in the functioning of the nitric oxide cycle, enhances the production of reactive oxygen and nitrogen species, reduces the activity of antioxidant enzymes, intensifies the processes of lipid peroxidation and leads to degradation of biological polymers of connective tissue in the gastric mucosa of rats. Intragastric administration of suspensions of nanosized silica oxide, carboline and hydrolysed lignin against the background of excessive intake of sodium nitrate and sodium fluoride leads to a decrease in the production of reactive oxygen and nitrogen species, to an increase of antioxidant enzymes activity, to reduction of lipid peroxidation intensity and prevents degradation of biological polymers of connective tissue in the gastric mucosa of rats. Only a suspension of nanosized silica oxide completely restores the functional state of the nitric oxide system. Keywords: sodium nitrate, sodium fluoride, enterosorbents, gastric mucosa.