Enhancement of human endometrial stromal decidualization by bestatin, an aminopeptidase-N inhibitor

We have re-evaluated the effects of bestatin, an aminopeptidase-N (CD13) in hibitor, on in vitro decidualization of normal human endometrial stromal ce lls by using an in vitro decidualization activity assay. Bestatin did not s how any effects on the viability of both the decidualizing stromal cells co -stimulated with 8-Br-cAMP and bestatin and the 8-Br-cAMP-induced deciduali zed stromal cells, or on prolactin release from the decidualized stromal ce lls. However, bestatin dose-dependently enhanced prolactin release from the decidualizing stromal cells co-stimulated with 8-Br-cAMP and bestatin. The se results indicate that bestatin enhances cAMP-mediated decidualization of human endometrial stromal cells and suggests that membrane aminopeptidase- N in the human endometrium is involved in the regulation of endometrial dif ferentiation by inhibiting cAMP-mediated decidualization signals in endomet rial stromal cells.