Changes of Gas Exchange Parameters and of Functional-Biochemical Properties of Erythrocytes in Dynamics of Experimental Anemia in Rats

In experiments on male Wistar rats, in a specially constructed computerized installation, O-2 consumption by the animals in comparison with changes of hematological, biochemical, and rheological blood properties is studied after anemization-acute blood loss (12-15% of the total blood mass). An increase of the O-2 consumption by the organism and tissues by 18-28% has been revealed for the first 7 days after the blood loss, in spite of a pronounced decrease of hematocrit and of the amount of erythrocytes and hemoglobin in peripheral blood by 20-25% of the initial level. There was a 5-10-fold increase of the content of immature erythrocyte forms-reticulocytes and a progressive rise of cell acidic resistance, which is characteristic of young erythrocyte forms. An in crease of O-2 consumption at a decrease of the blood oxygen capacity (a low hemoglobin level) seems to be due to the more efficient transport and yield of O-2 to tissues. At the 3rd and 7th day after the blood loss, activity of Na, K-ATPase has been found to increase by 60% and 20%, respectively. Anal ysis of the erythrocyte rheological properties has shown that the maximal firmness of aggregates (U-q) and the aggregation rate (1/T) decrease progressively beginning from 3 days after the blood loss; index of deformability (I-max) turned out to be elevated by 7-11%, probably due to an increase of the cell membrane elasticity. The conclusion is made that changes of erythrocyte rheological properties are interconnected with changes of the Na, K-ATPase activity and are directed at optimization of blood circulation in large vessels and the capillary network.