THE EXPRESSION CHARACTERISTICS AND THEIR BIOLOGICAL SIGNIFICANCE OF EPIDERMAL GROWTH FACTOR AND BASIC FIBROBLAST GROWTH FACTOR IN RAT SKINS AT DIFFERENT DEVELOPMENT STAGES

Objective To explore the localization and expression characteristics of epidermal growth factor(EGF) and basic fibroblast growth factor(bFGF) in rat skins at different development stages ( embryonic, newborn, adult). Methods Skins from embryonic, newborn and adult rats were taken, and detected by immunohistochemical technique. Results Positive immunohistochemical signal of EGF could be found in skins from embryonic, newborn and adult rats, mainly in the cytoplasm of the epidermal cells, fibroblasts, hair follicle epithelial cells, and endothelial cells. With the increase in age, the expression amount of EGF was increased. The positive signal of bFGF could be found in skins of newborn and adult rats, while the signal of bFGF in skin of embryonic rats was negative. Conclusion The results indicate that endogenous EGF plays important role in epidermal development in embryonic stage and wound healing in adult after injury. The negative expression of bFGF in skin of embryonic rat indicate that the absence of bFGF may be one of the reasons for the non-scar healing in embryonic stage.