Postimplantation development of mitomycin C-treated mouse blastocysts.
Treatment of morula-stage mouse embryos with mitomycin C (0.004-0.5 microgram/ml) in vitro resulted in a decrease in the number of inner cell mass (ICM) cells at the blastocyst stage. The trophectoderm population was reduced only at the highest dosage (0.5 microgram/ml) tested. Postblastocyst development in vitro was retarded: Fewer embryos formed trophoblastic outgrowth, and the ICM was poorly developed. The embryo transfer experiments demonstrated that a reduction in ICM cell numbers diminished the potential of embryogenesis. The presence of a sufficient number of trophoblasts and ICM cells in the blastocyst is therefore a prerequisite for successful implantation and embryogenesis. The mitomycin-treated blastocysts with only 70% of normal ICM cells developed to egg cylinders that were about half normal size, but by days 12-14 the body size of the surviving embryo was similar to that of the control embryo. Morphogenesis was retarded during the early organogenesis stages, but only a slight delay was seen in the treated embryo on day 12. Such observation strongly suggests that a restorative phase of growth and morphogenesis has occurred during the immediate postimplantation period.
D000818:Animals; D001755:Blastocyst / Q000187:drug effects*; D002452:Cell Count; D047108:Embryonic Development / Q000187:drug effects*; D005314:Embryonic and Fetal Development / Q000187:drug effects; D005260:Female; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D016685:Mitomycin; D008937:Mitomycins / Q000494:pharmacology*; D011247:Pregnancy
D008937:Mitomycins; D016685:Mitomycin