Influence of Metabolic Depletion of Red Blood Cells on Their Rheological Properties

We studied the influence of metabolic depletion of RBCs on their shape, stability cytoskeleton, anionic sites, deformation, aggregate morphology and aggregation. The blood was stored in the presence of an anticoagulant (sodium citrate) at 4°C during 14 days. It has been shown that during the storage of blood in RBCs the ATP level decreases, a large number of echinocytes and spheroechinocytes appear, the stability of their cytoskeleton and the content of anionic sites decreases. The deformation of RBCs in the artificial shear flow and of their aggregation in the autologous plasma decreases. At the same time, the pH and sodium level in the blood plasma decreases, and the potassium level increases. The plasma content of free hemoglobin increases. With the help of light microscopy, it was found that echinocytes of stored blood begin to aggregate with each other. The possible mechanisms RBC aggregation in the form of rouleaux and echinocytes are discussed.