[Several indicators of tissue oxygen during modeling of extravehicular activity of man].

Investigations of tissue oxygen indices during simulation of extravehicular activity (EVA) of cosmonauts demonstrated that breathing pure oxygen at approximately 280 mmHg elevates oxygen tension in capillary blood, and capillary-tissue gradient during physical work. Physical work alone stimulates tissue oxygenation due to, apparently, intensification of the processes of oxidative phosphorylation. The observed shifts in oxygen status reverse significantly within the first 5 min after completion of the experiment.

[Structural and functional disorders of erythrocyte membranes in simulated extravehicle space work].

The experimental data on a structural-and-functional status of erythrocyte membranes in ground-based simulation of human extravehicular activity (EVA) are discussed. The changes in the structure and function of erythrocyte membrane were determined from the fixation of lipophilic ions, specific activity of ion-transporting adenosine triphosphatases and content of the products of peroxide oxidation of lipids (POL) in plasma. On exposure to hypobaric hyperoxia during real EVA the membrane status changes are associated with the activation of a cascade of POL processes.

[Oxygen tension and water-soluble products of lipid peroxidation in blood of volunteers in hypobaric hyperoxia].

Oxygen tension in the arterial blood with transcutaneous method (tcPO2) and TBA-active products of venous blood plasma were measured during simulation of extravehicular activity. There was a parallel increase of tcPO2 and the level of TBA-active products upon introduction of hypobaric hyperoxia factor. Detrimental action of lipid peroxidation products on erythrocyte membranes can be one of the factors of anemia during space flight.