Davydova O. Temperature effect on membrane permeability of human erythrocytes and yeast Saccharomyces cerevisiae for cryoprotectants

The object of research - mechanisms of transmembrane transfer in human erythrocytes and Sacchаromyces cerevisiae yeasts cells, influence of temperature on the structural and functional state of their membranes. The aim of research is the experimental study of temperature effect on the permeability of human erythrocytes and Saccharomyces cerevisiae yeasts cells membranes for cryoprotectants with different hydrophobicity degree and on erythrocytes distribution density by sphericity index. Research methods: low-angle scattering method, physico-mathematical modeling of hypotonic hemolysis in solutions of penetrating and nonpenetrating substances, volumetric method, light microscopy method. It has been shown that the most expressed changes of the energy of activation of 1,2-propanediol and dimethylsulfoxide cryoprotectants passive permeability are observed within the range of temperatures 27-30 and 12-15C for native and pCMBS-treated erythrocytes. The temperature effect on the density of erythrocytes distribution by sphericity index has been first studied and the existence of critical temperature (15-12С) at which the part of cells with low sphericity index sharply increases is shown what was confirmed by the microscopic research. The permeability coefficients for glycerin, 1,2-propanediol, dimethylsulfoxide as well as the filtration coefficients in the media with these cryoprotectants for Saccharomyces cerevisiae yeasts cell membranes at temperatures of 10 and 25С are found. The received results of permeability coefficients of the studied cells membranes for water and cryoprotectants and their temperature dependences can be used for development of new and improvement of the existing protocols of low temperature preserving.