Effects of Epidermal Growth Factor and Interleukin-1α on Plasminogen Activator Secretion and Decidualization in Rat Endometrial Stromal Cells1

Prostaglandin E2 (PGE2) increases decidualization and net plasminogen activator (PA) activity in the medium of cultured endometrial stromal cells from ovariectomized rats sensitized for the decidual cell reaction. Because interleukin-1alpha (IL-1alpha) and epidermal growth factor (EGF) stimulate PGE2 production by these cells, the present study determined their effects on decidualization and on the levels of PA activity in the medium. Cells were treated with or without IL-1alpha (20 ng/ml) and EGF (40 ng/ml) for up to 72 h, and net PA activity in the medium and alkaline phosphatase (ALP) activity (a marker for decidualization) in the cells were measured. After 48 and 72 h of treatment with IL-1alpha, net PA activity levels decreased by 60% and 85%, respectively. EGF significantly increased net PA activity at 24, 48, and 72 h. ALP activity in the cells at 24, 48, and 72 h increased in response to IL-1alpha but not EGF. These results indicate that IL-1alpha, but not EGF, enhances decidualization of the cells as indicated by ALP activity. Moreover, they suggest that net PA activity in the medium is not a useful marker of decidualization.