Vitrification of mouse oocytes: improved rates of survival, fertilization, and development to blastocysts.
Rall and Fahy's (1985) vitrification procedure for the cryopreservation of 8-cell embryos was applied to unfertilized mouse oocytes. Unchanged, this method resulted in a mean of 24.1% of vitrified oocytes fertilizing and developing to blastocysts in vitro. Exposure of oocytes to the cryoprotectant media, but without the vitrification, resulted in 30.8% developing to blastocysts. Modifications to the durations of and media used in the dilution and equilibration steps of the procedure produced a final protocol giving a mean of 55.4% of vitrified oocytes and 72.4% of nonvitrified VS1-exposed oocytes developing to blastocysts; 85.7% of control oocytes develop to blastocysts. Osmotically induced damage was found to be the most important cause of loss of viability in these methods. Cooling of oocytes to 5-8 degrees C during the procedure had no significant effect on their viability. No parthenogenetic activation of oocytes occurred as a result of exposure to the procedure.
Shaw
P W
PW
Academic Department of Obstetrics and Gynaecology, Royal Free Hospital School of Medicine, London, United Kingdom.
Fuller
B J
BJ
Bernard
A
A
Shaw
R W
RW
D000818:Animals; D001755:Blastocyst / Q000502:physiology*; D002470:Cell Survival; D002478:Cells, Cultured; D015925:Cryopreservation / Q000379:methods*; D005314:Embryonic and Fetal Development; D005260:Female; D005307:Fertilization in Vitro; D051379:Mice; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D010312:Parthenogenesis