Immunohistochemical localization of epidermal growth factors in mouse olfactory epithelium

Our object was to clarify changes in epidermal growth factor (EGF) occurring in the olfactory epithelium with aging. We investigated the changes in EGF in the murine olfactory epithelium with aging by an immunohistochemical method. We examined six mice at each of the following stages: embryonal (embryonic days 14 and 16), neonatal (postnatal days 1 and 7), adult (postnatal weeks 5 and 12), and aged (postnatal years 1.5-2). The olfactory epithelium of each mouse was stained with anti-EGF polyclonal IgG using an immunohistochemical method. EGF were observed in the whole layer of the olfactory epithelium at all stages. The mesenchyme under the epithelium was stained in the embryonal stage, and the circumference of the olfactory gland cells was also stained, although weakly, in the adult stage. We believe that EGF contribute to cell proliferation, growth and turnover of the olfactory epithelium. However, the decrease in EGF was less than expected in the aged mice.