
TY  - JOUR
A1  - Martinez-Diaz, M. A. 
A1  - Ikeda, K. 
A1  - Takahashi, Y. 
T1  - Effects of cycloheximide treatment and interval between fusion and activation on <emph type="2">in vitro</emph> development of pig nuclear transfer embryos
JF  - Reproduction, Fertility and Development
JO  - Reprod. Fertil. Dev.
Y1  - 2002
VL  - 14
IS  - 4
SP  - 191
EP  - 197
KW  - cytoplasmic factors, electrical stimulus, nuclear status.
UR  - https://doi.org/10.1071/RD01114 
N2  - The effects of cycloheximide (CHX) treatment and the interval between fusion and activation on the development of pig nuclear transfer (NT) embryos constructed with enucleated oocytes and serum-starved granulosa/cumulus cells were examined. One group of couplets was fused and activated simultaneously (FAS) by a single electrical pulse (activation pulse). Another three groups of couplets were fused electricaly 1.5, 2.5 or 4.5 h before being subjected to the activation pulse (FBA). Each group was divided into two subgroups and incubated with or without CHX. The NT embryos treated with CHX showed a high and stable cleavage rate, regardless of the interval between fusion and activation; however, development to blastocysts was improved only when the NT embryos were subjected to FAS with CHX. These results indicate that CHX-sensitive events occurring shortly after FAS may be responsible for the development to blastocysts. Fusion pulse rarely activated M II oocytes, but rapidly dropped the p34cdc2 kinase activity in NT embryos. A pronucleus-like structure was observed 2-2.5 h after the activation pulse with CHX in NT embryos of both the FAS and FBA groups. Therefore, successive inactivation of M-phase promoting factor and cytostatic factor at a certain short interval may also play an important role in the development of NT embryos. 
ER  -

