IMMUNOHISTOCHEMICAL DEMONSTRATION OF EPIDERMAL GROWTH-FACTOR IN CHONDROCYTES OF MOUSE FEMUR EPIPHYSEAL PLATE

The distribution of epidermal growth factor (EGF) has been studied imm unohistochemically in chondrocytes of femur epiphyseal plate cartilage from adult mice. The chondrocytes of the resting and proliferating zo nes reacted positively, while those of maturing and calcifying zones s howed a relatively weak reaction. The immunoreaction was observed over both the cytoplasm and nuclei of resting and proliferating chondrocyt es and was prominent in the proliferating chondrocytes. These findings , taken together with the suggested synergistic action of EGF with oth er growth factors, raise the possibility that chondrocytes, particular ly in the proliferating zone, participate in a regulatory mechanism by EGF on cell division and growth in the epiphyseal plate cartilage.