Fiziologicheskiĭ zhurnal最新文献

The treatment of erythrocytes with different enzymes (neuraminidase, trypsin and papain) has been studied for its effect on the lipid peroxidation in their membranes, activity of antioxidant enzymes and on the ability of such erythrocytes to interact with neutrophilic leucocytes. It is shown that desialization of the membrane erythrocyte structures causes the intensification of lipid peroxidation in the membranes, decrease of their stability. Simultaneously, the interaction of neutrophils increases. The treatment with proteases causes the opposite changes. It is shown possible to split out the end molecules of sialic acids with exposure of the subterminal residues of B-galactose as a result of the effect of active oxygen forms. An assumption is advanced concerning the functional conjugation of the free-radical oxidation and proteolysis in provision of stability of the cell membranes.

A new turbodimetric proximate-micromethod has been used to determine six indices of blood coagulation and fibrinolysis (coagulation time, coagulation rate, maximal absorption, fibrinolysis rate, time of fibrin semilysis and complete lysis) in young donors, newborns, healthy pregnant women, healthy elderly and old age people. A positive correlation of the results obtained using the method suggested by the authors and conventional methods is found for the indices of blood coagulation and fibrinolysis. It is revealed that the above indices change depending on the physiological state of the human organism.

The cases of non-coagulation or only partial coagulation of blood plasma fibrinogen under the effect of thrombin have been revealed while examining the homeostasis-state in practically healthy elderly and old people and those with hypertonic disease. These cases have been analyzed. It is shown that the suggested method of fibrinogen determination in blood plasma using thrombin-like enzyme ancistrone-H extracted from venom of snakes (Agkistrodon halys halys) permits determining the fibrinogen content in blood plasma even in the cases connected with the presence of circulating coagulation inhibitors in plasma. The determination is not hindered by the introduction of exogenous heparin, including low-molecular heparins of the fraxiparin type.

The analysis of compression isotherms of lipid monolayers and thermodynamical estimation of the conditions of the formation of layered systems underlies the explanation of some details of lung surfactant work. When the chemical potential of the monolayer during compression reaches the value of the chemical potential of the liquid bilayer membrane free of the mechanical stress, the conversion of monolayer into bilayer phase commences by means of squeezing out of monolayer in subphase creating bilayer ripples. During inspiration when alveolar surface expands, ripples turn back. Hence, in the course of normal breathing the process is quazi-reversible. During forced breathing definite losses of surfactant in the subphase can occur due to closing of ripples tending to minimize the edge energy. On the other hand, the edge is the place of instability of bilayer where fusing of lipid aggregates with edge takes place enriching thus monolayer by the lipid molecules. It is suggested that the treatment of newborn respiratory distress syndrome necessitates the new ways of the enrichment of a monolayer with lipids from the subphase or the ways for inhalation of lipidic suspension having the morphology of the inverted phases.

The double bath method has been used to study reflex inhibition of cholinergic transmission in the guinea-pig ileum segment. It is shown that adenosine, noradrenaline, 5-methylfurmethide as well as acute hypoxia, which affect the oral part of the intestine are able to evoke two kinds of effects in its anal part firstly, the depression of cholinergic transmission, and secondly, the stimulation of non-adrenergic, non-cholinergic contractions. A preliminary treatment with capsaicin and with hexamethonium on the oral part of the gut prevents these effects, and the chymotrypsin abolishes these effects. A mechanism of this reflex descending inhibition of cholinergic transmission is realised apparently through the stimulation of the chemoreceptors in afferent capsaicin-sensitive nerves with participation of cholinergic interneurons and activation of the inhibitory, most probably vasoactive intestinal peptidergic (VIP) neurons in the enteric plexuses.

The influence of intestinal colonization by the Klebsiella pneumonia strain 50/59 on the characteristics of local and humoral immunity has been studied on CBA mice after weaning. Bacteria have been introduced intragastrally in doses of 1 x 10(6) bacteria per mice. Observations have been performed in dynamics during 11 days. They have shown that intestinal colonization induces significant elevation of the concentration of IgA in serum, intestinal content and percentage of splenocytes, expressing receptors of IgA, IgM, CD4 on the 7th day. On the 11th day a significant decrease in these parameters was observed. A conclusion is made that intestinal colonization is not indifferent for the whole organism and induces complex influences on its immune system.

The angioprotective efficacy of combined application of magnesium chloride and antioxidants during prolonged hypercholesterolemia has been investigated on the experimental model of atherosclerosis in rabbits. The application of magnesium chloride and acetate tocopherol from the very beginning of the atherogenic diet is shown to exert a pronounced angioprotective effect preventing the development of structural and functional changes in the aorta wall. If the treatment is initiated against the background of the well developed atherosclerotic symptoms, its efficacy is less pronounced but remains still on a quite high level. These data indicate that combination of magnesium chloride and antioxidants has not only protective action but can also induce partial regression of the developed atherosclerotic changes.

It is established that menstrual cycle influences the reactivity of the respiratory system. It is important to mark the changes during the menstrual cycle of sportswomen. Such observations can prevent the untimely and negative influence on the health during training. The days of menstrual cycle more or less favourable for the sports loading are marked. The parameters of cardiovascular system don't show common response to the hypercapnic test. Therefore, the parameters of hemodynamics cannot be used for predicting the physiologic status of sportswomen during menstrual cycle.

The effect of administration, of BIOMOS-VJ on the concentration of thyroxine, triiodothyronine, corticosterone, insulin and glucose in the blood serum of the normal state and under conditions of immobilization stress of young and aged Wistar's rats has been studied. The experiments have shown that the administration of preparation prevents the appearance of disturbances in endocrine system of the organism typical of stress such as a decrease in concentration of thyroid hormones and insulin and also a considerable increase in corticosterone and glucose concentration in the blood serum. On the basis of the results indicating the influence of BIOMOS-VJ on the endocrine system of young and aged Wistar's rats it is assumed that this preparation has gero-protected properties.

Neuropeptide Y (NPY) administration into the third brain ventricle of normal and castrated male rats decreases prolactin and LH secretion almost not affecting FSH. Simultaneous augmentation of hypophyseal response to LH-RH is observed. NPY effect on LH release is more pronounced in castrated animals as compared to normal ones. It is concluded that in the CNS inhibitory action of NPY prevails as regards to neuroendocrine control of gonadotropin and prolactin secretion. The obtained results allow NPY participation in feedback regulation of LH secretion in males.