The effect of sodium nitrite (NaNO₂) (0.07–3.50 mM) and sodium selenite (10 µM) on the oxidation of hemoglobin (Hb) and lipid peroxidation (LPO) in human red blood cells in vitro is examined. It was revealed that nitrites have a significant effect on oxidative processes in Hb and to a lesser extent in erythrocytes, and sodium selenite weakens the development of the nitrite-induced oxidative process in erythrocytes and reduces the formation of methemoglobin (MetHb) by 12–25%. Having a significant effect on the oxidative modification of Hb, nitrites at moderate concentrations do not lead to a noticeable increase in lipid peroxidation in erythrocytes. Under the influence of high NaNO₂ concentrations (3.50 mM), an increase in the accumulation level of MetHb by ten leads to an increase in the accumulation of thiobarbituric acid (TBA) active products by 40–70%. If at a low final concentration of nitrite (0.07 mM) there is no noticeable change in the content of total membrane-bound hemoglobin (oxyHb and MetHb), then at a moderate (0.70 mM) and high (3.50 mM) concentration these changes are obvious 10 and 15%, respectively. Introduced into the incubation medium before and after incubation with nitrite, sodium selenite with concentration 10 μM has a certain inhibitory effect on this process.

doi.org/10.32737/0005-2531-2020-2-67-73