Volumetric behaviour and survival of XXXX zygotes and embryos in hyperosmotic media.

@entity19 @entity1219 @entity3733 @entity969 @entity4372 @entity33778
Volume changes and survival of @entity19 zygotes and pre-implantation embryos were studied after their exposure to hyperosmotic media. Transfer of zygotes from culture medium to medium containing 1.5 M @entity3733 led to a rapid volume reduction to 60% of control values. After 10 min the volume was normal again, illustrating the rapid penetration of @entity3733 at room temperature. Re-transfer of zygotes equilibrated in 1.5 M @entity3733 to culture medium in one step doubled the volume. Twelve minutes later normal diameters were observed again. Volume changes were also recorded after transfer to media rendered @entity4372 by the addition of @entity1219 or @entity969 . A proportional decrease in volume was noticed up to 1500 mOsmol. A further increase in measured osmolarity up to 3100 mOsmol led only to limited further shrinkage of the zygotes (minimal volume observed was 27% of control volume). Addition of 1.5 M @entity3733 or 1.5 M @entity33778 had no influence on the final volume reaction to @entity1219 and @entity969 . Exposure to media with a measured osmotic value of 3200 mOsmol ( @entity1219 added) during 10 min did not prevent further development of the embryos to the hatched blastocyst stage. A solution of 4000 mOsmol proved lethal to nearly all embryos. Addition of 1.5 M @entity3733 to this medium did not have a protective effect against the osmotic stress at room temperature.
