A trial of histological preparation of early mouse embryos with the Technovit 7100 system

A reproducible procedure was devised for making histological preparations of early mouse embryos cultured in vitro. This method was characterized by use of a resinous embedding material, Technovit 7100, and a 96-well U-bottomed microplate, which enabled efficient rinsing and dehydration of fixed embryos without loss. Technovit 7100 polymerized or hardened at room temperature slowly enough to allow sedimentation of embryos to the bottom, which enabled more correct prediction of the place of the embryos at sectioning. The present method will lead to easier microscopic observation of early embryos in embryology.