Regulation of Epidermal Growth Factor (EGF) Binding Sites in Rat Granulosa Cells by Follicle Stimulating Hormone (FSH)
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Serono Symposia USA
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In the present study, we examined the effect of FSH on [125I]mEGF binding to rat granulosa cells (GC). The GC, isolated from diethylstilbestrol-treated immature female rats, were cultured with ovine FSH (NIADDK-oFSH-17) (1–300 ng/mL) in serum-free McCoy’s 5a medium for 48 h at 37°C and then were incubated with [125I]mEGF (0.05 μCi) for 18 h at 20°C to quantify EGF binding sites. After culture with oFSH for 48 h, the GC were cultured with or without mEGF (30 ng/mL) for 48 h at 37°C, then tissue plasminogen activator (tPA) activities in the conditioned media were examined by the fibrin overlay method. FSH significantly increased [125I]mEGF binding to rat GC in a dose-dependent manner, and EGF produced a dose-dependent increase in tPA activity compared to the control. Our findings suggest that functional EGF binding sites in rat GC are regulated by FSH and that FSH might influence folliculogenesis by regulating EGF receptors (EGF-R).
KeywordsEpidermal Growth Factor Receptor Epidermal Growth Factor Conditioned Medium Granulosa Cell Epidermal Growth Factor Binding
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© Springer-Verlag New York, Inc. 1992