INFLUENCE OF NANOSIZED SILICA OXIDE SUSPENSION ON NITRIC OXIDE PRODUCTION IN RATS TESTES DURING CHRONIC NITRATE-FLUORIDE INTOXICATION

In the Poltava region of Ukraine there is a high possibility of combined excessive intake of nitrates and fluorides, since the waters of the Buchaksʹkii aquifer are rich in fluorine ions, moreover, the Poltava region is a region with a developed agriculture. The purpose of this work is to determine the effect of nanosized silicon oxide suspension on the changes in the activity of nitric oxide cycle components, components, and, namely the total activity of NO-synthases (NOS), the activity of constitutive forms of NOS (cNOS), inducible form of NOS (iNOS), nitrate reductase, nitrite reductase, nitrite reductase, nitrite reductase in the testes of rats under the conditions of chronic combined nitrate-fluorodide intoxication. Materials and methods. The study was conducted on 15 mature male Wistar rats weighing 200-253 g. The animals were randomly divided into 3 groups of 5 animals in each. The first group received daily saline solution through a gastric tube. The second group (chronic combined intoxication group) received sodium nitrate and fluoride in a dosage of 500 mg / kg of sodium nitrate and 10 mg / kg of sodium fluoride. The third group against the background of chronic combined intoxication modelling additionally received a suspension of nanosized silicon oxide is a dosage of 100 mg / kg of active substance. Results. Chronic combined intoxication increases total NOS activity by 65.9% compared to the control group. The increase in NO production by NOS is the result of a 4-fold increase in iNOS activity, since the activity of cNOS under these conditions does not change significantly. Nitrite reductase-dependent NO production increases by 66.7%, nitrate reductase activity increases by 77.8%. Nitrite content in the testes homogenate grows in 2.17 times. Hydrolytic cleavage of L-arginine by arginase increases in 2.88 times. The introduction of nanosized silicon oxide suspension under the conditions of chronic combined intoxication did not statistically significantly change the total NOS activity and cNOS activity compared to the group exposed to chronic intoxication. However, iNOS activity reduces in 3.69 times. Nitrate reductase activity decreases in 1.6 times, while nitrite reductase activity decreases in 45%. The activity of arginases lowered in 2.38 times. The nitrite content of the testes cut down by 23.6%. Conclusions. Chronic combined nitrate-fluoride intoxication leads to the development of hyperproduction of nitric oxide in the testes of rats by activating the inducible isoform of NO synthase and nitrite reductases. The use of nanosized silica suspension during chronic combined intoxication is an effective method to correct nitric oxide overproduction in the testes of rats.