E12.5 whole mouse embryo culture.

Ex utero culture of postimplantation embryos remains one of the unsolved tasks in developmental biology. This technique may be required for infertility treatment, observation of embryo development and assessing the embryotoxicity of certain chemical agents. We describe novel method for E12.5 mouse embryos whole embryo culture system, which maintains embryo viability for 24 h. The culture system is based on the bubbling of pure oxygen through the culture medium. The oxygen was obtained by a chemical method. Each tube containing three embryos held 8 ml of culture medium composed of 6 ml of FBS, 2 ml of DMEM/F12, 80 μl of 40 % glucose and 30 μl of antibiotics (a mixture of penicillin 5000 UI/ml and streptomycin 5000 μg/ml). We observed initiation of auricle formation, as well as progression of eye development. Embryo viability was confirmed by the presence of heartbeat. The ratio of viable embryos after 24 h of culture was 27,78 %. However, many viable embryos exhibited massive hemorrhage attributed to oxygen insufficiency. The described culture system may be useful for the investigation of teratogenic compounds on the development of organs. Nonetheless, it is not suitable for ex utero culture of mouse embryos at more advanced stages due to the fact that embryos at such stages require more oxygen for the development than can be dissolved in the culture medium and consumed by embryos through diffusion. A potential solution to this issue is connecting the embryonic bloodstream to an oxygenator.