[RESTORATION OF SYMPATHO-PARASYMPATHETIC BALANCE IN HEART RATE VARIABILITY IN THE DEVELOPMENT OF PSYCHOEMOTIONAL STRESS AGAINST THE BACKGROUND OF TAURINE IN EXPERIMENT].

In this fragment of the study, the change in the ratio of low (LF) and high frequency (HF) waves to the heart rhythmogram during prolonged immobilization (5 hours) of sexually mature white non-linear rats was studied by spectral analysis of heart rate variability, which causes psychoemotional stress and the accompanying vegetative equilibrium shift, indicating on the dysregulation of the sympatho-parasympathetic balance without and against the background of daily intraperitoneal injection of taurine (50 mg/kg) and its participation in the mechanisms of adaptive processes in the early poststress period (from 1 to 14 days). Spectral analysis of both absolute and relative indices of the I-th group (stress without taurine) revealed significant shifts in the frequency spectrum. On the first day after immobilization, the total power of the spectrum decreased by 4.3%, the HF component by 33.3%, and the level of VLF and LF-components increased by 25.5% and 25%, respectively, compared to the norm. On the 14th day after the immobilization, there is a decrease in tension, but the LF component is still above the norm by 5%. Calculations of the percentage ratios of the absolute values of the spectrum at different times of the post-stress period against the background of taurine injection showed that in the initial stage (immediately and on the first day after stress) a strong shift of activity toward sympathization occurs, and the absolute value of LF and VLF in the spectrum increased by 23,1% and 10.9% respectively. However, the complete restoration of the vago-sympathetic balance with the daily application of taurine occurs already on the 7th day after immobilization. The beneficial effect of taurine on the cardiovascular system was revealed when examining the scatterogram of the regression dependence of the heart rate, which revealed a smaller variation in heart rate and its stabilization on the 7th day after immobilization. Thus, the use of taurine immediately after stressful reactions is necessary to accelerate adaptive processes in the early post-stress period to prevent the development of stress pathology.

[THE ROLE OF TAURINE THE PROCESS OF ADAPTATION OF VISCERAL SYSTEMS UNDER PSYCHO-EMOTIONAL STRESS IN RAT].

In recent years the identification of regulatory mechanisms of the general adaptation syndrome, manifesting itself as the response of an organism to drastic changes in the environment and leading to emotional stress, acquires a special significance. The control over visceral functions plays a particular role in stress reactions because of emerging threat of violation of neurodynamic balance of sympathetic-para- sympathetic relationships with their most sensitive element - the heart. Quick adaptation to stress helps to restore not only the sympathetic-parasympathetic homeostasis but also the energy metabolism. One of the essential components, activating metabolic processes, is taurine. This paper considers the descending influence of the paraventricular nucleus (PVN) on neuronal reactions of the solitary tract nucleus (NTS), the first linking pathways of visceral sensitivity, the mechanisms of central control over visceral reactions by mathematical model analysis of heart rate variability (MMA HRV) as well as morpho-histochemical changes in brain structures integrating and regulating the visceral sphere (PVN of the hypothalamus and the amygdala) under psycho-emotional stress without and with intraperitoneal injection of taurine (50 mg/kg). Acute and semichronic experiments were conducted on white nonlinear rats under 5-hour- long immobilization psycho-emotional stress. A highly defined centralization of vegetative HRV parame- ters (HR, IVR, INRS) was revealed, these parameters being normalized on days 7 and 14 at the background of taurine injections. The interaction and interdependence of the central regulatory mechanisms of cardiovascular reactions are shown as well as a considerable protective effect of taurine on promoting early restoration of adaptive properties of the central and peripheral segments of visceral sensitivity under development of long-term psycho-emotional stress.