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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.

The aim of the present study was to evaluate the effects of interleukin (IL)-1beta on the production of vascular endothelial growth factor (VEGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) in the human fallopian tube. Human oviductal epithelial cells (OECs) and oviductal stromal fibroblasts (OSFs) were isolated from ten premenopausal patients. The secretion of VEGF and sFlt-1 by cultured OECs and OSFs in response to IL-1beta and IL-1 receptor antagonist (IL-1RA) was measured using an enzyme-linked immunosorbent assay. The secretion of VEGF and sFlt-1 was detected in cultured OECs and OSFs under untreated conditions; secretion of these angiogenic modulators was significantly stimulated with IL-1beta administration in these cells. IL-1beta-induced production of VEGF and sFlt-1 by these cells was significantly inhibited by the addition of IL-1RA. The present findings suggest that IL-1beta in the local environment may stimulate oviductal vascular permeability by inducing the production of VEGF by oviductal cells via both autocrine and paracrine mechanisms. Simultaneous upregulation of sFlt-1 secretion by these cells after IL-1beta stimulation may prevent an excessive upregulation of vascular permeability. The modulation of the ratio of VEGF and sFlt-1 in the fallopian tube may contribute to the normal and pathological processes of oviductal fluid secretion by regulating oviductal vascular permeability during the menstrual cycle and during the peri-implantation period.

Our objective was to clarify the physiological role of vascular endothelial growth factor (VEGF) by amnion-derived (WISH) cells. WISH cells were cultured, and the effect of epidermal growth factor (EGF), mitogen-activated protein (MAP) kinase kinase or extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitors (U0126) or phosphatidylinositol (PI) 3-kinase on the production of VEGF was examined. VEGF was assayed by ELISA. The activation of MAP kinase and akt, which is phosphorylated by PI 3-kinase, were detected by Western blot analysis using anti-phosphorylated MAP kinase antibody and anti-phosphorylated akt antibody. In the time course of VEGF production following EGF treatment, VEGF production showed a significant increase only after 16 (p < 0.01)-32h (p < 0.01). EGF increased the production of VEGF by WISH cells in a dose-dependent manner. The MAP kinase and akt activity were determined by treatment with EGF. VEGF production was significantly decreased following pretreatment with U0126 or wortmannin for two hours before treatment with EGF (p < 0.01, p < 0.01). WISH cells appeared to produce VEGF via a mechanism involving tyrosine kinase activation of EGF receptor and MAP kinase or PI 3-kinase. It is suggested that VEGF may contribute to the neovascularization and proliferation of the placenta and gestational tissue, and EGF may play an important role in regulation of VEGF production in the placenta.