THE ERYTHROCYTE AS PHYSICAL SYSTEM - KINE TICS OF TRANSMEMBRANE OXYGEN-TRANSPORT

It is inferred from analysis of normal physiology data that erythrocyt e membrane permeability for the oxygen in human organism must decrease at least 1000 times after oxygenation in the lungs. And the cell memb ranes of other tissues are also capable to change their permeability f or the oxygen. The kinetics of blood oxygenation and deoxygenation is investigated in order to check this conclusion. Measurements of blood oxygenation kinetics together with oxygen tension in blood plasma allo ws to determine average value of membrane permeability decrease being equal 70 times. Biological expediency of fluctuation of the erythrocyt e membrane permeability is discussed. A method of determination of opt ical oxymeters calibration and hemoglobin-oxygen equilibrium curve for the blood is proposed. It does not require the oxygen equilibrium bet ween the blood plasma and the erythrocyte cytoplasm and uses only read ings of a calibrated oxymeter. Variation of non-equilibrial state of t he erythrocyte during the oxygen saturation is considered as the cause of the membrane permeability fluctuation. Erythrocyte parameters, suc h as its volume, substances concentration, transmembrane potential, ar e shown to depend on the amount of the substances not penetrating thro ugh the membrane and on osmotic pressure. A hypothesis of the transmem brane potential influence on the membrane permeability is proposed. Th e external electric field is shown experimentally to accelerate the bl ood deoxygenation.