MORPHOLOGICAL AND BEHAVIORAL ANALYSIS OF THE PROTECTIVE EFFECTS OF BACTERIAL MELANIN IN A RAT MODEL OF PARKINSON'S DISEASE.

A comparative study of the morphological and functional state of the microvasculature of the substantia nigra pars compacta of the brain (SNc) and bone marrow of rats was carried out using the rotenone model of Parkinson's disease (PD) and with subsequent administration of bacterial melanin (BM). The detection of microvasculature was carried out according to the histoangiological method of Chilingaryan. Animal behavior was studied using a cylinder test. An analysis of morphometric data showed that, in comparison with control animals, experimental animals with rotenone dysfunction showed an increase in capillary diameters and a general reduction in the capillary link in SNc. Behavioral tests have shown that the animals with rotenone intoxication exhibit a form of behavior inherent in PD (freezing, immobility, apathy). Under the influence of BM, the diameter of the capillaries in the SNc approaches the norm, and the capillary link is restored. Due to the protective effect of BM in rats with rotenone intoxication, the trophism of the brain tissue increases as a result of the approach of the lumen of the vessels to the norm and the opening of new branches in the capillary network, an increase in the density of capillaries, which ensures the safety of nerve cells. Animal behavior indicators are close to normal. A comprehensive analysis of cytogenetic data of rat bone marrow was also carried out. In animals with PD, compared to controls, there is a significant increase in the amount of polyploid cells (PC) and a decrease in the level of mitotic index (MI), which usually manifests itself in inflammatory processes and is accompanied by inhibition of bone marrow hematopoiesis. Under the influence of BM, a tendency towards normalization of MI was noted and a significant decrease in the percentage of PC was obtained, which possibly indicates its beneficial effect. The data obtained suggest that BM can be used as a therapeutic agent in the treatment of PD.

ASSESSMENT OF RAT BRAIN MORPHOFUNCTIONAL STATE IN A PARKINSON'S MODEL: INFLUENCE OF THERAPEUTIC AGENTS OF ANIMAL AND SYNTHETIC ORIGINS.

In neurodegenerative diseases, particularly in Parkinson's disease (PD), antinociceptive centers are often implicated in neurodegeneration, leading to persistent pain unresponsive to narcotic substances. This study investigated the periaqueductal gray matter (PAG) and the nucleus raphe magnus (NRM), components of the brain's antinociceptive system. In conditions of rotenone intoxication (an experimental PD model), morphological changes in intracellular structures were observed in PAG and NRM neurons, indicating metabolic disorders characteristic of PD (alterations in the shape and size of neuronal bodies and processes, disruption of acid phosphatase activity in neuron cytoplasm). Under the influence of bacterial melanin and in combination with synoestrol, positive changes in structural properties were observed in PAG and NRM neurons compared to the rotenone model of PD. This included the preservation of the morphological characteristics typical of these brain regions, with cells exhibiting shapes and sizes close to normal. Furthermore, under the influence of these therapeutic agents, an increase in phosphatase activity in cell cytoplasm was detected, indicating an acceleration of metabolic processes (metabolic activation) disrupted by rotenone intoxication. The data obtained suggests that bacterial melanin and synoestrol may act as potential neuroprotective agents against PAG and NRM neurons in the rat brain in the rotenone model of PD. Further research is needed to elucidate the mechanisms of action of therapeutic doses and propose their use in the treatment of PD, either in isolation or combination therapy.

INFLUENCE OF LONG-TERM VIBRATION ON THE ACTIVITY OF THE SUPERIOR VESTIBULAR NUCLEUS NEURONS UNDER THE CONDITIONS OF STIMULATION OF THE HYPOTHALAMUS NUCLEI.

Prolonged vibration exposure leads to alterations of the central control mechanisms of both the vestibulo-ocular and the vestibulo-autonomic systems, including a change in the hypothalamic-vestibular relationships associated, in particular, with the supraoptic nucleus and paraventricular nucleus. Post-vibration disturbances of the vestibular function are largely due to adaptive changes in neurotransmitter activity. The dynamics of spike activity of single neurons of the superior vestibular nucleus (SVN) in response to high-frequency stimulation of the paraventricular and supraoptic hypothalamic nuclei after long-term vibration exposure were analyzed. Analysis of impulse activity revealed the prevalence of tetanic potentiation in the responses of SVN neurons to high-frequency stimulation of paraventricular and supraoptic nuclei of rats. Exposure of animals to vibration led to a decrease in the number of neurons with tetanic potentiations and significant dominance of post-tetanic potentiation. Morphological and histochemical results showed that under hypothalamic stimulation in the SVN neurons of rats exposed to vibration, there is an increase in metabolism and dephosphorylation processes in the cellular structures of the studied brain area, which ultimately provides optimal conditions for the processes of cell survival and regeneration.

[Physiological basics of sport activity of professional football players].

Maintenance of motor activity by autonomic nervous system is adjusted, mainly, by congenital reflexes. But alongside with inborn reactions to muscular work at formation of motor skill the specific vegetative components are formed to the given kind of sport activity. The aim of our research was revealing those physiological features which are characteristic for an organism of the high skilled sportsmen, with large experience of training and competitive activity. At tested football players have been measured some parameters of external respiration and cardiovascular system. In our investigation it is shown, that programming of the same productivity of work and the same effect are achieved by unequal vegetative support and a different combination of separate components of the general vegetative reaction. Definition and a due estimation of these intermediate parameters in conditions of rest and at physical loading enables objective judgement about a functional condition of the sportsman, about weak parts in system of maintenance of a homeostasis of an organism and directions of accomplish the functioning of the basic effectors.