[Mechanisms of changes of microcirculation in rats under acute methemoglobinemia].

It was investigated the features of microcirculation and mechanisms it's conditioned, under acute administration of sodium nitrite in 5 mg of dry substance per 100 g of body weight. It was shown that acute administration of sodium nitrite leads to the development of methemoglobinemia, arterial and venous hypoxemia, and severe tissue hypoxia. Increase in the diffusion path O2 at methemoglobinemia is caused due to significant hyperhydratation of lung air-blood barrier and its individual layers, and is accompanied by a decrease in both components of the diffusion capacity of the lungs for oxygen: its membrane and blood components. It was revealed that the administration of sodium nitrite has a double effect, leading to inactivation of hemoglobin, as well as to microcirculatory disturbances associated primarily with changes in the regulation of vascular tone. In this initial perfusion per unit volume of tissue per time unit intrinsic for the organism defines a set of mechanisms which are responsible for changes in tissue blood flow under methemoglobinemia.

[The state of cyclic nucleotide system and morphofunctional changes of lung and heart tissues in hypoxia of different genesis].

It was investigated the intercommunication of the functional state of cyclic nucleotides (CN) system and morphofunctional states of lung and heart tissues and influence on these state of lipid peroxidation processes and adenylate cyclase system activity under development in organism of the hypoxic states of different genesis. Obtained dates testify that with the changes of cAMP and cGMP concentrations, and also with their ratio the level of hyperhydratation of air-blood and blood-tissue barriers under the used influence on the organism are closely correlated. Intercommunication of the cyclic nucleotides system functioning and tissues oxygen consumption at the used influences carries sufficiently difficult and ambiguous character. It was shown that exactly at blood loss in lung and heart tissues there were the parallel diminishing of concentrations both cAMP and cGMP. It is accepted to correlate with a favorable histological dynamics. Exactly under these conditions the correlation of CN concentrations is possible to consider balanced and sent to limitation of displays of unfavorable influence of blood loss on investigated tissues ultrastructure. So, there is a tissue specific and depending from the type of influence on the organism character of intercommunication of the functional state of cyclic nucleotides system and morphofunctional states of lung and heart tissues.

[Changes of the brain stem neurocytes in newborn rats in the conditions of experimental model of hypoxia during neuroprotective correction].

The work includes a research of morphological and immune-histochemical specifics of baby rats' cerebral structures in the conditions of experimental hypoxia model and with the administration of Cerebrocurin. It was ascertained that the most pronounced changes in the form of pericellular and perivascular edema, spongiform loci and loci of necrosis, with the phenomena of apoptosis and aponeuroses, occurred during severe hypoxia. Administration of Cerebrocurin in baby rats, which experienced moderate hypoxia, causes a decrease in pathological changes in cerebral structures and the approximation of the level of CD95 APO-1/Fas and Bcl-21 gene expression to their level in intact animals.

[Effect of normo- and hypobaric hypoxia on ultrastructure of the lung and myocardial tissue].

Priority of effect of oxygen concentration and/or atmospheric pressure changes on morphofunctional state of lung tissue and myocardium under exasperate influence on the organism, which lead to the development of different hypoxic states, was investigated. It was shown, that the intermittent hypoxia without barometric pressure lowering influence on ultrastructure of tissues less traumatically, then hypobaric hypoxia. Additional acute hypoxic influence and acute hemorrhage accompanied with less significant structural violations in lung tissue and myocardium of animals, which were adapted to hypobaric hypoxia. Stress exchanges were less considerable after normobaric hypoxic trainings.

[Connection of functional characteristics and ultrastructure of the lung and myocardium in hypoxia and srtess].

The estimation of changes in breathing, circulation, gas exchange, lipid peroxidation, which can be connected with or determined by morphofunctional state of lung tissue and myocardium in rats under acute hypoxic hypoxia, acute dose hemorrhage and immobilization stress were made. Such approach is important not only from theoretical point of view, for the elucidation and definition of mechanisms which are responsible for function of oxygen-transport systems under unfavorable influences on the organism, but present particularly practical interest. The exposure of correlation between structure and function in investigated organs may permit to forecast the availability of some ultrastructural violations under ventilation or circulation changes in the organism.

[Age-dependent differences of the ultrastructural changes in the myocardium after hypoxical preconditioning and ischemia-reperfusion of the isolated heart in rats].

Recently we evidenced the ability of acute systemic hypoxia to induce phenomenon of delayed cardioprotection in rats. Age-dependent peculiarities were studied in 6 and 12 month old rats exposed to hypoxical preconditioning (10% O2, 1 or 3 h). In 24 h isolated hearts were ischemized 30 min and then reperfuzed 40 min, with or without iNOS blocker 1,3-PBIT (50 nmol/l). It was shown that hypoxic preconditioning dose-dependently injured myocardial ultrastructure, and induced delayed cardioprotection, strongly marked after 3 h preconditioning. Blockade of iNOS as mediator of delayed cardioprotection led to mitochondrial stimulation and attenuated protection. In mature aged rats, myocardial injury and protection had been individually variable, mitochondria were more damaged and stimulated to biogenesis, and incomplete autophagy was typical as distinct from young rats.

[Genetically determined organ-specific changes of some tissue morphometric characteristics under the various exogenous influences].

Organ-specific alterations of ultrastructure and morphofunctional condition in different organism's tissues, which could evidence of the genetic factors inclusion under the development of different hypoxic condition in organism, were investigated. The dates obtained indicated the marked organ-specific "structure" reaction of tissues, cells and organelles under various exogenous influences. Such reactions confirm the presence of different genes expression which account for ultrastructure alterations; its activity is determined by a type, intensity, duration of influence as well as organ belonging. Ultrastructural alterations are mainly determined by tissue and cell factors but not by genetically determined system reactions; it is confirmed by various reactions on external factors in animal tissues with different genetically determined oxygen consumption level or genetically determined adaptation to middle-altitude conditions.

[Effect of intermitent hypoxia on ultrastructure and prooxidant-antioxidant balance in the soft tissue of the periodontium in acute immobilization stress].

The changes of prooxidant-antioxidant balance and morphofunctional state of soft tissue of paradontum under the acute immobilization stress, intermittent hypoxia and its complex influence were investigated. It was shown, that intermittent hypoxia can stimulate own endogenous mechanisms of nonspecific resistance, such as antioxidant protection in soft tissue of paradontum. Normalization of the prooxidant-antioxidant balance under immobilization stress after intermittent hypoxia essentially improved the morphofunctional state of tissue investigated with decrease of edema and improvement of mitochondria apparatus ultrastructure.

[Effect of cerebrokurin and lipin on changes in the rat brain mitochondria in experimental model of hypoxia].

The authors carried out the sudy on morphofunctional changes of mitochondria of neurocytes of the brainstem of rats under experimental model of hypoxia and administration of Cerebrokurin and lipin. Cerebrokurin administration to rats which underwent severe chronic hypoxia lead to increase in mitochondria diameter and considerable increase of their area in the unit of volume as well it resulted in renewal of myelin sheaths. Use of Cerebrokurin and lipin in animals which underwent moderate hypoxia lead to probable increase in mitochondria area in the unit of volume in comparison with animals not treated with these agents.

[Correlation of tissue respiration and some mitochondria stereometric characteristics of the lung tissue in different modifications of hypoxic hypoxia].

In experiments on the adult white laboratory rats the correlation of tissue respiration and some morpho- and stereometric characteristics of mitochondria in lung tissue under breathing by air and gas mixture with 7% O2 in N2 was investigated. The following agents were used as modulators: indomethacin, a blockator of cyclooxygenase way of arachidonic acid metabolism; quercetin and linoleil of hydroxamic acid, blockators of lipooxygenase way ofarachidonic acid metabolism; taurine, an antihypoxant and energy source under hypoxic conditions; lipin-antihypoxant with significant membrane protective effect. It was shown, that the respiration intensity of tissue homogenate, not only of its mitochondrial fraction, closely connected with structural organization of mitochondria. It was demonstrated that changes of O2 concentration in gas mixture lead to the alteration of interrelation between O2 consumption and stereometric characteristics of mitochondria: in normoxia the intimate correlation was established with number of mitochondria and its total surface; in hypoxia such correlation was established with mitochondria diameter and number of structurally damage organelles. Pharmacological modulation factors play in this process not so significant role.

[Correlation between the thickness of air-blood barrier of the lung and main indices of respiration during changes in oxygen concentration]. / Vzaiemozv'iazok tovshchyny aerohematychnoho bar'iera lehen' ta osnovnykh pokaznykiv dykhannia pry zmini kontsentratsiï kysniu.

In experiments on adult white laboratory rats the correlation among external respiration, gas exchange and blood O2 transport under breathing by air and gas mixtures with 40%, 14.5%, 11% and 7% O2 in N2 was investigated. It was demonstrated the narrow structural-functional interrelation in oxygen transport system. The thickness of air-blood barrier (ABB) correlates not only with the external respiration and diffusion capacity of lung, but with parameters, which are not directly connected with the state of lung tissue, such as oxygen content in venous blood, VaO2/VO2 and even with circulation volume. The existence of narrow correlation of ABB thickness and the most of investigated parameters permits to prognosticate the availability of structural disturbances in the presence of external respiration, gas exchange and blood O2 transport changes.

[Effect of polymer material thermal destruction products on external respiration and acid-base status of blood]. / Vplyv produktiv termodestruktsiï polimernykh materialiv na zovnishnie dykhannia ta kyslotno-luzhnyi stan krovi.

In experiments on white laboratory rats the influence of fluor-, cyan- and sulfur-containing gaseous products, formed under thermodestruction of synthetic materials in normal and high environmental temperature on external respiration and some parameters of acid-base blood values was investigated. It was shown, that external respiration, due to considerable it depression, could not compensate neither hypoxic state, accompanied by hypoxemia, nor hypercapnia and acidosis, developed under the influence of toxic agents both in normal environmental temperature and in hyperthermia.

[Changes in the local nonspecific immune response to post-traumatic inflammation during treatment]. / Zminy mistsevoï nespetsyfichnoï rezystentnosti u posttravmatychnomu vohnyshchi v dynamitsi likuvannia.

Clinical investigation have been done in adult patients with broken mandible during 3 weeks of conservative treatment with aluminum splints (1st group, n = 17) or steel splints (2nd group, n = 16) in comparison with health adults (control group, n = 18). The neutrophil emigration into alterative locus and their degranulation as well as phagocytic activity of peripheral blood neutrophils were tested. It was found that aluminum splint application caused the intensive inflammation and then the depression of local host defense reactions. Treatment with steel splints did not lead to neutrophil function depletion or to hyper-intensification of inflammatory reaction in patients. The increased values of neutrophil reactions were normalized in this group at the final period of the treatment. The examined trial ensures our accurate method in treatment of patients with broken mandible. The determination of local host defense state may be proposed as preferable simple express-method of evaluation of immune status, treatment efficiency and prognosis in these patients.

[Effect of potassium channel openers on lysosomal function and morphology during acute hypoxic hypoxia]. / Vplyv moduliatoriv aktyvnosti kaliievykh kanaliv na morfofunktsional'nyi stan lizosom pry hostrii hipoksychnii hipoksiï.

It was studying the effect of fluorinecontain pinacidil analogs (PF-5 and PF-10), which are the K(+)-channel openers, on morphofunctional lysosomes state at lung and heart tissues. The investigation was made on white pubertal rat-males under acute (30 min) hypoxic hypoxia (7% O2 [symbol: see text] N2). The application of PF-5 and PF-10 under acute hypoxic hypoxia leads in lung and myocardium tissues to morphofunctional changes of lysosome system in investigated cells, which were connected with decreasing of enzyemia. It, partly, may be explain by increasing of connected enzyme forms synthesis, because such forms are the functional latent, so the output of enzymes in blood under unfavourable conditions increased.