Injection of epidermal growth factor (EGF) into 24-day rabbit fetuses (5 μg, im or ip) induced accelerated maturation of the lung. On sacrifice at day 27, there was greater distensibility and stability on deflation associated with the appearance of a complement of type II cells approaching that of the rabbit at term. EGF treatment had no demonstrable effect on body weight or lung weight in this group of animals. Saline-injected control fetuses were not affected significantly.Speculation
EGF is capable not only of promoting epithelial cell growth but also differentiation in the fetal rabbit lung. It may be an important hormone in the maturation of the lung and capable of protecting the prematurely delivered fetus against the development of hyaline membrane disease.