Cyclic changes in expression of mRNA of vascular endothelial growth factor, its receptors Flt-1 and KDR/Flk-1, and Ets-1 in human corpora lutea

Abstract

Objective: To evaluate the expression of mRNA of vascular endothelial growth factor (VEGF), its receptors Flt-1 and KDR/Flk-1, and Ets-1 in human corpora lutea.Design: Prospective laboratory study.Setting: University hospital in Japan.Patient(s): Women with regular menstrual cycles who underwent hysterectomy.Intervention(s): Fifteen corpora lutea were obtained during hysterectomy (5 in the early luteal phase, 5 in the mid-luteal phase, and 5 in the late luteal phase).Main Outcome Measure(s): Expression of VEGF, Flt-1, KDR/Flk-1, and Ets-1 in human corpora lutea on northern blot analysis or immunohistochemistry.Result(s): Human corpora lutea in early luteal phase and mid-luteal phase had high VEGF mRNA expression. Expression of VEGF mRNA was significantly reduced in the late luteal phase. Immunohistochemistry showed that VEGF protein was expressed mainly in granulosa lutein cells and faintly in thecal lutein cells. Staining of VEGF protein was decreased in human corpora lutea in the late luteal phase. Expression of Flt-1 and KDR/Flk-1 mRNA was increased in the early luteal phase and mid-luteal phase and decreased in the late luteal phase. Immunohistochemistry showed that Flt-1 and KDR/Flk-1 proteins were expressed mainly in granulosa lutein cells and faintly in thecal lutein cells and endothelial cells in the early luteal phase and mid-luteal phase; their protein staining was reduced in the late luteal phase. Expression of Ets-1 mRNA changed similarly to VEGF and its receptor mRNA in human corpora lutea during the luteal phase.Conclusion(s): Levels of mRNA of VEGF and its receptors Flt-1 and KDR/Flk-1 in human luteal cells may be related to luteal function.