OVARIAN-STEROIDS REGULATE THE EXPRESSION OF BASIC FIBROBLAST GROWTH-FACTOR AND ITS MESSENGER-RNA IN FIBROBLASTS DERIVED FROM UTERINE ENDOMETRIUM

The role of stromal cells in basic fibroblast growth factor (FGF) supp ly for endometrial neovascularization during the menstrual cycle was i nvestigated. The concentrations of intracellular and secreted FGF, and FGF mRNA expression were determined in fibroblasts derived from uteri ne endometrium as a substitute for stromal cells. The influence of sex steroids on protein and mRNA expression was investigated. The concent ration of FGF and its mRNA expression in the fibroblasts was significa ntly increased by oestradiol, and these increased concentrations were diminished by progesterone. It is suggested that oestrogen stimulates FGF secretion from the stromal cells, an effect which is inhibited by progesterone. Therefore; endometrial neovascularization might be parti ally regulated by stromal-derived FGF under the influence of sex stero ids, through a paracrine cell-to-cell interaction.