Serum Serotonin as a Biomarker of the Efficacy of PAP-Therapy in Sleep Apnea Syndrome.

Serum serotonin levels were determined by HPLC in 30 patients with diagnosed obstructive sleep apnea syndrome before and after 3-month course of PAP-therapy and in 14 subjects without obstructive sleep apnea symptoms. It was found that elimination of hypoxic conditions was associated with an increase in serotonin level. The results demonstrate the effectiveness of PAP-therapy during sleep and allow assessing the role of serotonin as a potential biomarker of intermittent hypoxia during sleep.

[The relationship of hemodynamic parameters of periodontal microvascular bed and lipid peroxidation products in adolescents with arterial hypertension].

The Aim: Of the study was to establish the relationship of hemodynamic parameters of periodontal tissues and lipid peroxidation products in adolescents with arterial hypertension (AH).

Methods: The study included 132 adolescents (average age 14.51±1.

Comparison of Reactivity of the Lipid Peroxidation-Antioxidant Defense System in Normal and Hypertensive Rats at Different Stages of Stress-Reaction.

We compared changes in the parameters of LPO-antioxidant defense system at various stages of the stress response in mature male ISIAH rats (hereditary stress-induced arterial hypertension) and WAG rats in 3 h (stage of anxiety) and 7 days (resistance stage) after a 3-h single immobilization in the supine position. It was found that post-stress reactivity of the nonspecific stress-limiting LPO system is different in normotensive and hypertensive rats. ISIAH rats, irrespective of the stage of the stress-reaction, demonstrated more intense LPO reactions (accumulation of TBA-reactive products) and reduced antioxidant defense parameters (low content of lipid-soluble vitamins, increased oxidized glutathione content) in comparison with the corresponding parameters in WAG rats.

Evaluation of Lipid Peroxidation-Antioxidant Defense System Depending on the Stage of Stress Reaction in Hypertensive ISIAH Rats.

The stages of stress reaction (anxiety and resistance) were reproduced on the model of stresssensitive hypertensive ISIAH rats. Analysis of the experimental data showed an increase in activity of the antioxidant defense system in ISIAH rats: total antioxidant activity of the blood and superoxide dismutase activity increased at the stage of anxiety and then decreased during the resistance stage.

Coupling of Lipoperoxidation Reactions with Changes in Arterial Blood Pressure in Hypertensive ISIAH Rats under Conditions of Chronic Stress.

Mature normotensive male WAG rats and stress-sensitive hypertensive ISIAH rats were exposed to "everyday life stress" modelled by alternation of immobilization and adaptation. Increased LPO intensity (increased content of substrates with unsaturated double bonds and primary and secondary LPO products) and reduced content of some antioxidant protection components (reduced retinol level and GSH/GSSG ratio) were revealed in the blood of ISIAH rats. These changes correlated with elevated mean BP.