CHANGES OF BIOCHEMICAL INDEXES AND FUNCTIONAL ACTIVITY OF HEART OF HIGH AND LOW-RESISTANCETO ACUTE HYPOXIC HYPOXIA IN RATS OF DIFFERENT SEX IN IMMOBILIZATIONAL STRESS

Abstract

Introduction. Determining the mechanisms of damaging the influence of stress on the heart in persons with different reactivity can contribute to the development of individual methods of correction.

The aim of the study–to determine the effect of immobilization stress on changes in peroxide lipid oxidation, antioxidant defense and ECG indices in rats of different sex with high and low resistance to hypoxia (HR, LR).

Research Methods. Stress was modeled 4 times by an hour immobilization of rats on a back down with an interval of 24 hours. In the heart, the diene and triaene conjugates, schiff bases, TBA-active products, superoxide dismutase (SOD), catalase activity were determined. ECG was recorded.

Results and Discussion. In control HR males, in comparison with LR, lower activity of lipid peroxidation (LPO), higher activity of SOD was observed; in HR-females, in comparison with LR, more products of LPH, SOD, less activity of catalase. Immobilization led to oxidative and carbonyl stress, more in males, compared to females. In the study of ECG only when stressed in HR-females increased the amplitude of the wave R, the deviation of ST relative to the isoline; In LR, the heart rate increased, the duration of the interval RR and QTc decreased.

Conclusions. Interval immobilization of rats leads to oxidative and carbonyl stress in the heart, but the mechanisms of their development depend on resistance to hypoxia and sex. With immobilization stress, changes in ECG are noted only in females.