NITRIC OXIDE SYNTHESIS INTENSITY ASSESSMENT BY THE CONTENT OF ITS TERMINAL STABLE METABOLITES IN THE BLOOD OF RATS UNDER FLUORIDE INTOXICATION.

: The aim of the research was to evaluate the intensity of nitric oxide synthesis in the experiment by the content of its terminal stable metabolites in the blood of rats exposed to sodium fluoride. The studies were conducted on adult Wistar rats weighing 180-220 g, subjected to oral exposure by means of a probe with aqueous solutions of sodium fluoride (SF) daily for 60 days at a dose of 1/10, 1/100 and 1/1000 DL50, respectively, of 20 mg/kg, 2 mg/kg and 0.2 mg/kg body weight. Oral administration of SF to rats at doses of 1/10 and 1/100 of DL50 leads to an increase in blood plasma levels of nitrite and nitrate anions during the first 30 days, indirectly indicating the excessive production of nitric oxide, which in the initial period of intoxication can perform compensatory role, but in the future can cause pathological reactions associated with the activation of oxidative stress. The reduction of nitrite and nitrate anions at the end of the long-term effects of SF indirectly indicates a decrease in the generation of nitric oxide, which may be due, in particular, to the increase in the concentration of peroxynitrite as a result of the use of nitric oxide in reaction with a superoxide anion radical and a deficiency of antioxidant enzymes.