Fiziologicheskiĭ zhurnal最新文献

Changes in efficiency of mental activity and general and brain hemodynamics in students of physico-mathematical faculty when they solve problems on math analysis for 3 hours under conditions of pronounced neuro-emotional tension (NET) during examination have been experimentally studied. The results obtained from these studies are considered. It is shown that relation of higher nervous activity and general and brain hemodynamics is determined by efficiency of the activity, its energy provision (intensity), the level of NET and the rate of automated psychic reactions. A conclusion is made that efficiency of the activity is a basic system-forming factor in a relation arising between higher nervous activity, on the one hand, and general and brain hemodynamics, on the other hand. The higher is the efficiency, the lower are power requirements and the level of NET and the higher is the rate of automated psychic reactions: mental working capacity.

The experiments on Wistar rats have shown that intragestral injection with mannitol hypotonic solution (20 mmol/l) causes the significant activation of Na+, K(+)-ATPase of duodenum and distal intestine epithelial cells, kidney cortex cells, but does not affect the brain cortex of Na+, K(+)-ATPase activity. Simultaneously the activator of enzyme (AE) enters blood serum of rats, its activity is revealed by blood serum addition to homogenates of tissues of control rats. It is assumed that AE is produced in duodenal and intestinal mucosa released to blood after stimulation of mucosal surface by hypotonic solutions and included into the osmoregulation processes on the Na+, K(+)-ATPase level.

Efficiency of anti-anemic drug Ferrum Lack when using it alone or together with enterosorbent Uvesorb has been studied on the model of iron deficiency anemia (IDA) in pregnant rats. It is stated that three-fold blood-letting in total volume of 6 ml carried out prior to pregnancy causes symptoms of IDA. Over a period of the whole pregnancy the concentration of hemoglobin and the concentration of erythrocytes were lower than in intact pregnant rats. Tissue hypoxia characterized by disturbance of terminal microcirculation, capillary tissue diffusion and oxygen utilization was observed in pregnant rats with anemia model. Dysfunctional shifts in the system lipid peroxidation (LPO)-antioxidant protection (AOP) as noncompensated process of free-radical oxidation of lipids were revealed in parallel. A comparative estimation of results from treatment in groups of animals which were given and not given enterosorbent Uvesorb together with anti-anemic drug Ferrum Lack permitted determining the presence of anti-anemic and antihypoxic effects in both groups, though the latter was more pronounced in animals which were given enterosorbent. Various results were revealed relative to changes in the LPO-AOP system. When using drug Ferrum Lack alone, the content of products of LPO-lipid hydroperoxides and malonic dialdehyde increased in blood, whereas in group of animals which were given enterosorbent the number of these products was observed to significantly decrease.

The characteristics of ballistic food-procuring movements were studied in albino rats. After electrolytic destruction of ventromedial nucleus of thalamus (VM) of contralaterally preferred extremity the number of attempts and frequency of movements were determined to increase with a decrease of their duration. The restoration of parametres of movements took place during a week. A phase structure of movements also undergoes some modifications: in the case of invariance of initial ballistic components, conditioned by strict links of programme one-side switching off of VM tells on the following components, subject to correction. Re-teaching, requiring the modification of motor programme caused considerable difficulties in rats with switched off VM. The obtained results illustrate the significance of rats' VM in the formation and realization of motor programmes.

The experiments on 40 Wistar male rats with acute circulatory-hemic hypoxia induced by hemorrhage in amount of 15-20% of circulating blood volume were carried out to study the state of lysosomal apparatus of the liver and lung tissues as to changes in activity of acid phosphatase (AP), a marker enzyme of lysosomes. In the case of such a hemorrhage the common activity of AP decreased by 37% in the liver tissue and by 41% in the lung tissue, the free activity increased by 30% and 25%, and bound activity decreased by 84 and 70% in homogenates of the corresponding tissues. Under these conditions the activity of the above lysosomal enzyme in blood plasma became five times as higher as control. A conclusion is made concerning the circulatory-hemic hypoxia influence on the lysosomal membrane's structures of organ's tissues cells (as one can judge by the example of liver and lungs), which is observed in an increase of permeability of lysosome membrane and causes a sharp increase of AP enzymia in blood plasma.

It is shown that the membrane potential level, ionic current and membrane conductance depend on the cell cycle stage both in Misgurnus fossilis L. embryos and in Xenopus laevis Daudin embryos by the microelectrode technics. Allowing for the role of the adenylate cyclase system in the membrane potential oscillations and ion conductance of membranes, some series of experiments for analysis of the inhibitor have been carried out.

Lipine, a new antihypoxic drug, has been studied for its effect on respiration and pulmonary gaseous exchange in 47 newborn children, health and with respiratory distress syndrome stresses (SRD) after perinatal asphyxia. It is shown that lipine inhalations cause a considerable increase in duration of respiratory cycle, decrease of respiration frequency, ratio of ispiration di time, to expiration time, increase of alveolar ventilation volume and decrease of respiratory dead space ventilation volume in all lung ventilation volume in newborns with SRD, to a larger degree pronounced in premature children. A conclusion is made on the positive effect of lipine on the state of respiration function and gaseous exchange in lungs in newborn children with symptoms of SRD.

The age peculiarities of higher nervous activity (HNA) have been studied in 777 1st-10th form pupils at school of general education. Heterogeneity and nonuniformity of changes in indices are peculiar to age dynamics of HNA. The most intensive changes are stated in junior and senior forms.

The carried out investigation of the peripheral blood indices in one-month old rabbits against the background of reactivity suppression of the hypothalamic-hypophyseal-adrenocortical system in response to 12-hours immobilization has shown an interrelation between the activity of the hypothalamic-hypophyseal-adrenocortical system and the reaction of the lysosomal apparatus of neutrophilic leukocytes under stress conditions.