Biology of Reproduction, Vol 11, 18-21, Copyright © 1974 by Society for the Study of Reproduction

Differential Sensitivity of Preimplantation Mouse Embryos In Vitro to X-Irradiation

¹ Department of Physical Biology, New York State Veterinary College, Cornell University, Ithaca, New York

A technique was established for in vitro culture of preimplantation mouse embryos, and their development under these conditions was characterized. The embryos were recovered from superovulated mice, cultured and X-irradiated at various stages of development. Preimplantation embryos were also irradiated and grown in vivo. The investigation included a measurement of differential sensitivity of various stages of development and a comparison of the effects of radiation delivered to embryos in vivo and in vitro. The following LD₅₀ values (based on development to the blastocyst) were determined for embryos irradiated in vitro: 390 rads, two-cell stage, 570 rads, four-cell stage; 325 rads, morula stage. The LD₅₀ values for embryos irradiated and grown in vitro were: 420 rads, two-cell stage; 640 rads, four-cell stage; 340 rads, morula stage.