title: Comparison of ethylene glycol, 1,2-propanediol and glycerol for cryopreservation of slow-cooled mouse zygotes, 4-cell embryos and blastocysts.
abstract: The aim of the study was to analyse the toxicity, the osmolar and cryoprotective activity of ethylene glycol (ETG) in terms of survival rate (SR), cleavage rate (CR) and expanded blastocysts percentage (EBP) of mouse embryos. Early mouse embryos and blastocysts were slowly cooled with ETG, 1,2-propanediol (PROH) or glycerol, and thawed. The Van t'Hoff curve for 1.5 mol/l ETG showed recovery of initial volume within 4 min. No differences were observed in CR and EBP of ETG-exposed compared with non-exposed mouse zygotes. The SR of zygotes frozen with PROH was significantly better than with ETG (92% and 60% respectively; P < 0.01), and a significantly better EBP was achieved for blastocysts frozen with glycerol compared with ETG (75% and 50% respectively; P < 0.05). For 4-cell stage embryos, no differences were observed in SR and EBP between ETG and PROH. Higher EBP was observed for 4-cell stage embryos (53%) frozen with ETG compared with pronucleate stage (19%) and blastocysts (48%). Low toxicity, good SR and EBP were observed for mouse embryos frozen with ETG, the best results being obtained at the 4-cell stage. At other embryonic stages, PROH and glycerol respectively seemed to provide better results.
authors.affiliation: Fertility Clinic and Laboratory of Biology and Psychology of Human Fertility, Hopital Erasme French Speaking Free University Brussels, Brussels, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Emiliani
authors.forename: M
authors.initials: M
authors.lastname: Van den Bergh
authors.forename: A S
authors.initials: AS
authors.lastname: Vannin
authors.forename: J
authors.initials: J
authors.lastname: Biramane
authors.forename: Y
authors.initials: Y
authors.lastname: Englert
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000502:physiology; D015925:Cryopreservation; D003451:Cryoprotective Agents; D004622:Embryo, Mammalian / Q000502:physiology*; D019855:Ethylene Glycol / Q000633:toxicity; D005260:Female; D005990:Glycerol / Q000633:toxicity; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D019946:Propylene Glycol / Q000633:toxicity; D015053:Zygote / Q000502:physiology
chemical_list: D003451:Cryoprotective Agents; D019946:Propylene Glycol; D019855:Ethylene Glycol; D005990:Glycerol