Human oocyte vitrification: the permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification.
OBJECTIVE
To determine the permeability of human metaphase II oocytes to ethylene glycol and water in the presence of ethylene glycol, and to use this information to develop a method to vitrify human oocytes.


METHODS
An incomplete randomized block design.


METHODS
A university-affiliated assisted reproductive center.


METHODS
Women undergoing assisted reproduction in the Center for Reproductive Medicine at Shandong University.


METHODS
Oocytes were exposed to 1.0 molar ethylene glycol in a single step and photographed during subsequent volume excursions.


METHODS
A two-parameter model was employed to estimate the permeability to water and ethylene glycol.


RESULTS
Water permeability ranged from 0.15 to 1.17 microm/(min.atm), and ethylene glycol permeability ranged from 1.5 to 30 microm/min between 7 degrees C at 36 degrees C. The activation energies for water and ethylene glycol permeability were 14.42 Kcal/mol and 21.20 Kcal/mol, respectively.


CONCLUSIONS
Despite the lower permeability of human metaphase II oocytes to ethylene glycol compared with previously published values for propylene glycol and dimethylsulfoxide, methods to add and remove human oocytes with a vitrifiable concentration of ethylene glycol can be designed that prevent excessive osmotic stress and minimize exposure to high concentrations of this compound.
Comparative Medicine Center and Department of Veterinary Pathobiology, University of Missouri at Columbia, Columbia, Missouri 65211, USA.
Steven F
SF
Mullen
Mei
M
Li
Yuan
Y
Li
Zi-Jiang
ZJ
Chen
John K
JK
Critser
D000328:Adult; D002463:Cell Membrane Permeability / Q000502:physiology*; D015925:Cryopreservation / Q000379:methods*; D019855:Ethylene Glycol; D005260:Female; D006801:Humans; D008677:Metaphase; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D027724:Reproductive Techniques, Assisted; D014867:Water
D014867:Water; D019855:Ethylene Glycol