title: The optimal equilibration time for mouse embryos frozen by vitrification with trehalose.
abstract: To determine the best equilibration time in the cryoprotectant before rapid cooling, 8-cell mouse embryos were exposed to a vitrification solution containing ethylene glycol, Ficoll and trehalose in modified phosphate-buffered saline at 5 degrees C for varying periods of time. They were frozen using an ultra rapid freezing method, thawed in a 20 degrees C water bath and cultured for 24 h with 5-bromo-2-deoxyuridine. Embryo development and the number of sister chromatid exchanges, a sensitive indicator of genetic damage, were observed. The results demonstrated that embryo development after freezing and thawing was similar among the groups exposed for periods of 5-40 min. However, the number of sister chromatid exchanges was significantly smaller in the group exposed for 5 min, indicating that this was the safest equilibration time in the vitrification solution.
authors.affiliation: Department of Obstetrics and Gynecology, Yamagata University School of Medicine, Iida-Nishi, Japan.
authors.forename: G M
authors.initials: GM
authors.lastname: Ishida
authors.forename: H
authors.initials: H
authors.lastname: Saito
authors.forename: N
authors.initials: N
authors.lastname: Ohta
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: M M
authors.initials: MM
authors.lastname: Ito
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Nakahara
authors.forename: M
authors.initials: M
authors.lastname: Hiroi
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000633:toxicity; D004249:DNA Damage; D004622:Embryo, Mammalian / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D008297:Male; D051379:Mice; D012854:Sister Chromatid Exchange; D012996:Solutions; D013997:Time Factors; D014199:Trehalose / Q000633:toxicity
chemical_list: D003451:Cryoprotective Agents; D012996:Solutions; D014199:Trehalose