@article{oai:niigata-u.repo.nii.ac.jp:00002041,
 author = {Niimura, Sueo and Futatsumata, Nana},
 issue = {3},
 journal = {Journal of mammalian ova research},
 month = {},
 note = {The process of early development in diploid parthenogenetic mouse embryos from the 2-cell to the blastocyst stages was observed by time-lapse videomicrography, and was compared with that in fertilized embryos. Parthenogenetic 2-cell embryos cleaved and developed to 8-cell embryos after 23.0 hrs of culture. Transformation of blastomeres occurred at the 8-cell stage: namely, outer blastomeres were flattened. The embryos compacted at the morula stage, and then developed to blastocysts after 54.0 hrs of culture. A slit in the zona pellucida was formed 42.7 hrs after blastocyst formation, and trophectoderm cells protruded out of the zona pellucida through the slit. Protrusion of trophectoderm cells from the zona pellucida could arise from either side, polar trophectoderm or mural trophectoderm. After 7.0 hrs, the blastocysts completely escaped from the zona pellucida in either state, expansion or contraction. Fertilized 2-cell embryos showed morphological changes similar to those of parthenogenetic embryos and developed to blastocysts after 51.9 hrs of culture. Fertilized blastocysts took a significantly shorter time, 31.1 hrs, to start hatching, but required a significantly longer time, 23.8 hrs, to complete hatching, compared with parthenogenetic blastocysts. Hatching patterns of fertilized blastocysts were consistent with those of parthenogenetic blastocysts, except that hatching began with protrusion of trophectoderm cells from small holes in zonae pellucidae of fertilized blastocysts. From these results, it was confirmed that the developmental ability of early diploid parthenogenetic embryos prepared by the treatment with ethanol and cytochalasin B is comparable to that in fertilized embryos.},
 pages = {124--129},
 title = {Time-Lapse Videomicrographic Observations of Parthenogenetic Mouse Embryos during Early Development},
 volume = {16},
 year = {1999}
}