Experimental investigation of some systemic effects of nitric oxide inhalation

The goal of this work was to study the influence of nitric oxide inhalation on parameters of blood proand antioxidant systems in rats under both an intact condition and experimental thermal injury. We studied 40 Wistar rats that were divided into four equal groups. The intact group was subjected to no manipulation exñept a single blood sampling, main group I was subjected to inhalation of a air mixture containing 20 ppm of nitric oxide for 10 days, the control group was subjected to thermal injury and conventional treatment, and main group II was subjected to thermal injury and daily inhalation of nitric oxide (20 ppm) for 10 days. We studied the intensity of lipid peroxidation in the blood plasma, the total antioxidant activity, the peroxide resistance of erythrocytes, the level of malondialdehyde in the blood plasma and erythrocytes, and the activity of superoxide dismutase. It was shown that daily inhalations of a mixture containing a low concentration of nitric oxide (20 ppm) modified blood oxidative metabolism in healthy and burned rats. We hypothesized that the activation of lipid peroxidation in erythrocytes accompanied by a pronounced increase in the catalytic activity of superoxide dismutase is a unified response of healthy and burned rats to exogenous nitric oxide exposure. We also observed a moderate prooxidant effect in the blood plasma of healthy animals comparable to that in the erythrocytes of these rats. In the case of thermal injury, oxidative stress tended to be corrected after the end of the course of inhalation.