Postimplantation Rat Whole-Embryo Culture Assay

Method Description

Rat embryos with 1 to 5 somites are used in this method. In general, these embryos are relatively sensitive for xenobiotics as compared to older embryos. During 48 hours of culture, major aspects of organogenesis occur, including e.g. heart development, closure of the neural tube, development of ear and eye, brachial bars and limb buds. Interference during this period may lead to general retardation of growth and development or to specific malformations in one or several organ anlagen.
Embryos are cultured in rotating containers, thus facilitating the exchange of the culture medium with the gaseous phase above. The latter is essential for optimal oxygenation of the culture medium in view of the increasing demand for oxygen of the embryo. After culture, the morphology of the embryos is carefully assessed. Comparison of control embryos with exposed embryos forms the basis for conclusions regarding the embryotoxicity of tested compounds.