Short-term recovery from a volume increase in the mouse zygote: Characteristics of regulatory volume decrease in vitro.

Abstract

Mouse zygotes have been shown to recover from an imposed increase in volume, a process known as a regulatory volume decrease or RVD, via separate but functionally coupled Cl- and K+ channels. The objectives of this thesis were to further determine some of the characteristics of these Cl- and K+ channels involved in RVD in the mouse zygote. It was proposed that the Cl - channel in mouse zygotes was a swelling-activated Cl -/organic osmolyte channel like that found in many other cells. A method developed by Passantes-Morales et al. (1993) was used, in which a large extracellular concentration of one of a number of organic osmolytes was added to the experimental media, and the ability of the zygote to perform RVD in the presence of each was determined. A number of organic compounds demonstrated an inhibition of RVD, and thus, identified a number of organic compounds which might function as organic osmolytes in embryos. To directly test whether swelling of zygotes increased their permeability to organic osmolytes; the permeability in swelled zygotes was compared to that in non-swelled zygotes, using 3H glycine. (Abstract shortened by UMI.)