THE PRESENCE OF PLATELET-DERIVED ENDOTHELIAL-CELL GROWTH-FACTOR IN HUMAN ENDOMETRIUM AND ITS CHARACTERISTIC EXPRESSION DURING THE MENSTRUAL-CYCLE AND EARLY GESTATIONAL PERIOD

Decidualized tissues are characterized by the intensive outgrowth of t he microvasculature. Several angiogenic factors are assumed to be invo lved during the drastic change in the vasculature occurring in the pro cess of decidualization. We examined the possible role of platelet-der ived endothelial cell growth factor (PD-ECGF), a known angiogenic fact or, during the process of early decidualization in humans. The express ion of PD-ECGF in human endometrium was demonstrated by Western blot a nalysis, a marked increase being found in decidualized endometrium. Im munohistochemical staining showed that PD-ECGF immunoreactivity was pr esent mainly in decidualized endometrial stromal cells. We established a primary cell culture of human endometrial stromal cells which were differentiated into decidualized cells in vitro by the addition of pro gesterone. In this cell culture system, progesterone augmented the exp ression of PD-ECGF in a dose-dependent fashion. The addition of proges terone also resulted in an increased release of prolactin, a well-know n marker for decidualization. These findings suggest that PD-ECGF may play a physiological role as a possible angiogenic factor in the proce ss of decidualization of human endometrium.