title: Permeability of mouse oocytes and embryos at various developmental stages to five cryoprotectants.
abstract: To assess the permeability of mouse oocytes and embryos, matured oocytes and embryos at various stages of development were placed in five cryoprotectant solutions at 25 C for 25 min. From the cross-sectional areas of the oocytes/embryos, the relative change in volume was analyzed. In oocytes, shrinkage was least extensive and recovery was quickest in the propylene glycol solution, showing that propylene glycol permeates the oocytes most rapidly. Dimethyl sulfoxide, acetamide, and ethylene glycol permeated the oocytes slightly more slowly than propylene glycol. The oocytes in glycerol shrunk extensively and then expanded marginally, indicating slow permeation. The volume changes of 1-cell and 2-cell embryos were similar to those of oocytes, showing little change in permeability. In 8-cell embryos, the volume recovered much faster than in the earlier stages especially in glycerol and acetamide. In morulae, the volume recovery was much faster in glycerol and in ethylene glycol; in ethylene glycol, the extent of shrinkage was small and the recovery was fast, indicating an extremely rapid permeation. Although the permeability of oocytes/embryos generally increased as embryo development proceeded, the degree of increase varied greatly among the cryoprotectants. Interestingly, the volume change in propylene glycol was virtually unaffected by the stage of development. Such information will be valuable for determining a suitable protocol for the cryopreservation of oocytes/embryos at different stages of development.
authors.affiliation: Laboratory of Animal Science, College of Agriculture, Kochi University, Japan.
authors.forename: Prudencio B
authors.initials: PB
authors.lastname: Pedro
authors.forename: Eiji
authors.initials: E
authors.lastname: Yokoyama
authors.forename: Shi En
authors.initials: SE
authors.lastname: Zhu
authors.forename: Naoko
authors.initials: N
authors.lastname: Yoshida
authors.forename: Delgado M
authors.initials: DM
authors.lastname: Valdez
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Tanaka
authors.forename: Keisuke
authors.initials: K
authors.lastname: Edashige
authors.forename: Magosaburo
authors.initials: M
authors.lastname: Kasai
mesh_terms: D000081:Acetamides / Q000493:pharmacokinetics; D000818:Animals; D001755:Blastocyst / Q000187:drug effects / Q000378:metabolism; D001757:Blastomeres / Q000187:drug effects / Q000378:metabolism*; D002463:Cell Membrane Permeability; D048429:Cell Size / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000493:pharmacokinetics*; D004121:Dimethyl Sulfoxide / Q000493:pharmacokinetics*; D047108:Embryonic Development / Q000187:drug effects / Q000502:physiology; D019855:Ethylene Glycol / Q000493:pharmacokinetics; D005260:Female; D008677:Metaphase; D051379:Mice; D008813:Mice, Inbred ICR; D008846:Micromanipulation / Q000295:instrumentation; D009028:Morula / Q000187:drug effects / Q000378:metabolism*; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism*; D019946:Propylene Glycol / Q000493:pharmacokinetics
chemical_list: D000081:Acetamides; D003451:Cryoprotective Agents; D019946:Propylene Glycol; C030686:acetamide; D019855:Ethylene Glycol; D004121:Dimethyl Sulfoxide