STUDY OF THE CRYOPROTECTING PROPERTIES OF ANTIFREEZE GLYCOPROTEINS FROM WHITE SEA COD CADUS-MORHUA AT LOW-TEMPERATURE FREEZING OF MOUSE EMBRYOS

The effect of antifreeze glycoproteins on morphological preservation a nd viability of mouse embryos cryopreserved in liquid nitrogen was stu died. Cryomicroscopic observations indicated that as distinct from the cryoprotector dimethylsulfoxide antifreeze glycoproteins cause phenom ena typical of vitrification (absence of visible crystallization, tran sparency of medium). The embryos frozen in the presence of freeze glyc oproteins had after thawing a higher morphological preservation (87,5% ) than those frozen wich 1M and 3M dimethylsulfoxide (53,8 and 71,1%, respectively). However, they were nonviable and did not develop in cul ture. A high viability after cryoconservation was achieved only when a ntifreeze glycoproteins (20 mg/ml) were used together wich dimethylsul foxide (3M). In this case, the number of viable embryos, which develop ed in culture to the stage of compact morula and blastocyst, was 65,0% , i.e. two and four times higher than in the presence of 3 M and 1 M d imethylsulfoxide, respectively.