PROPERTIES OF ERYTHROCYTES FROZEN IN COMBINED MEDIUM WITH POLYETHYLENE GLYCOL AND DIMETHYLSULFOXIDE

Osmotic, antioxidative and morphological characteristics of erythrocytes frozen in liquid nitrogen in a medium containing polyethylene glycol-1500 or in combined medium with polyethylene glycol-1500 and dimethylsulfoxide were studied. During freezing in medium containing polyethylene glycol-1500, significant rate of erythrocytes damage, glutathione loss by the cells during cryopreservative washing-out and penetration increasing of rest of cells for H^sup +^ ions were reported. At the same time no significant increasing of malonic dialdehyde concentration and valuable change of indices of glutathione-metabolized enzymes activity during freezing in two indicated media were found out. At additional introduction of DMSO into medium, damage rate of erythrocytes during freezing decrease significant keeping the sufficient osmotic, antioxidative and morphological properties of the remained part of cells after cryopreservative washing-out. The findings enable to suggest that osmotic and morphological properties retention of erythrocytes being frozen in combined medium with polyethylene glycol-1500 and dimethylsulfoxide were provided by penetration of the latter into the cells and weakening of hypertonic stress, stimulated by NaCl and polyethylene glycol-1500 concentration during freezing.