Cherkashina Y. Effect of cryoprotectants and modifiers of cytoskeleton-membrane complex on erythrocyte state under osmotic and temperature shock conditions

The thesis covers the investigations of the effect of cryoprotectants, membrane and cytoskeleton modifiers and anion transport inhibitors on sensitivity of erythrocyte to the change of osmotic and temperature conditions of the medium. Chemical modification of erythrocytes was performed by treating the cells with IAA, PCMB, NEM. Modification of anion transport was done using the inhibitor of anion transport, dipyridamole. As the medium components there were used sodium salts of chloride, sulphate and sucrose as well as cryoprotectants (PEG-3000, PEG-1500, PEG-400, glycerol, 1,2-propanediol, DMSO). Obtained during this research results testify to the fact that non-penetrating cryoprotectants reduce sensitivity of human erythrocytes to hypertonic cryohemolysis during the whole incubation time meanwhile penetrating ones reduce the level of hypertonic hemolysis at initial incubation stage in electrolyte media. Modification of erythrocyte membranes with IAA and PCMB has been established as resulting in elimination of membrane temperature transition at 9±1 C. Cell incubation in the media containing cryoprotectants (PEG-3000, PEG-1500, PEG-400, glycerol, 1,2-propanediol, DMSO) has been demonstrated as not leading to significant changes in the rate of H+ ion transport into erythrocytes, but causes a rise in the rate of ion release of H+ ions within the Jacobs-Stewart cycle.