NERVE GROWTH-FACTOR IN THE DEVELOPING CRANIOFACIAL REGION OF THE MOUSE EMBRYO

Nerve growth factor (NGF), demonstrated by immunohistochemistry, appea rs during craniofacial development of the mouse in several embryonic t issues. First, NGF is present in the neural and placodic tissues of ea rly embryos. At later stages, NGF staining appears in premuscular and precartilaginous blastemata, as well as in the tooth germs. The presen ce of NGF in muscular primordia is probably in relation with its putat ive trophic effect on target tissues. However, cartilaginous expressio n of NGF supports the view that this molecule could play a role in the regulation of preskeletal differentiation.