Abstract: | The function of granulosa cells is regulated by various hormones and growth factors. Our aim is to clarify the regulation of vascular endothelial growth factor (VEGF) production induced by heparin-binding EGF-like growth factor (HB-EGF) and amphiregulin (AR) in a human granulosa cell line, KGN. KGN cells were cultured and incubated for 24 h with HB-EGF and AR. The levels of VEGF in the culture media were measured by an enzyme-linked immunosorbent assay. The activation of MAP kinase in KGN cells was detected by Western blot analysis. VEGF production was significantly increased by HB-EGF or AR alone in a dose-dependent manner, whereas it was decreased by AG1478 or U0126. The MAP kinase activity was increased by treatment with HB-EGF or AR. The results suggested that VEGF is induced by HB-EGF and AR through mechanisms involving MAP kinase. The increase in VEGF may contribute to neovascularization, which in turn would promote various ovulation phenomena as well as follicular growth. |