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

Prostaglandin E 2 (PGE 2 ) 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-1α (IL-1α) and epidermal growth factor (EGF) stimulate PGE 2 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-1α (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-1α, 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-1α but not EGF. These results indicate that IL-1α, 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.