We studied the state of the LPO-antioxidant defense system in men aged from 46 to 55 years. The main group included patients with obstructive sleep breathing disorders. The state of the antioxidant defense system was assessed by measuring the blood levels of LPO substrates with conjugated double bonds, conjugated dienes, ketodienes and conjugated trienes, MDA, retinol, α-tocopherol, reduced and oxidized glutathione, SOD activity, and the level of total antioxidant activity of blood. Calculation of antioxidant potential helps to identify the processes of "oxidative stress" in the main group, which is a pathogenetic substantiation for including antioxidant drugs in the complex therapy of patients with OSBD.

Specific features of LPO were studied in Mongoloid and Caucasian patients with type 1 diabetes mellitus. The intensity of LPO in Mongoloid patients was lower than in Caucasians: the level of primary and intermediate products was by lower 1.53 and 1.83 times, while total antioxidant activity was elevated by 1.44 times, which was also supported by oxidative stress coefficient (1.35 in Mongoloids and 2.32 in Caucasians). These differences suggest that differentiated approach is required for the treatment of these patients.

LPO processes and blood antioxidant status were studied in reproductive-age women with the hypothalamic syndrome. The control group consisted of somatically healthy women without reproductive disorders. Female patients with the hypothalamic syndrome were characterized by an imbalance in the LPO-antioxidant defense system, which aggravated the course of the underlying disease.

The data of foreign studies over the last 15 years devoted to endogenous synthesis and biological role of hydrogen sulfide in micromolar quantities which complemented the already two well-known gas transmitters -OH and NO are presented in

Investigation of emotional sphere and LPO processes in adolescents of both sexes aged 14-17 years suffering from essential hypertension revealed pronounced changes in the emotional status associated with dysregulation in the LPO-antioxidant protection system. The emotional sphere in adolescents with hypertension was characterized by increased anxiety in combination with emotional lability, tendency to depression, and aggressive reactions. The most meaningful parameters describing significant differences between the groups of healthy and hypertensive patients in parameters of LPO-antioxidant protection system were fatty acids with double bonds, antioxidant activity, and retinol. Statistically significant opposite correlations between the emotional status parameters and components of LPO-antioxidant protection system were revealed.