A staining procedure for nerve fibers in whole mount preparations of the medaka and chick embryos.

A simple and reproducible technique is described by which the nerve fibers in small fish and chick embryos are revealed in whole mounts. The materials were fixed, washed, pre-treated by various procedures and finally stained immunohistochemically by using an antibody directed against neurofilament protein. The cranial, spinal and sympathetic nerve fibers were stained. In the medaka, pit organs were also stained. Moreover, it was possible to stain the nerve fibers in the same material repeatedly. By this method, the three dimensional structures of the nerve fibers and their relationships to other structures can be readily observed.