Comparative Studies on the In Vitro Decidualization Process in the Baboon (Papio anubis) and Human(2)
Baboon endometrial stromal cells demonstrate specific immunohistochemical staining for alpha smooth muscle ac-tin (aSMA) during early pregnancy. Alpha SMA staining eventually disappears at Days 32-40 of pregnancy. This is coincident with the time these cells produce IGFBP-1, particularly at the implantation site. In a simulated-pregnant baboon, hCG, estrogen, and progesterone were sufficient to induce aSMA expression in stromal fibroblasts, but IGFBP-1 expression was not evident. These in vivo studies suggest that the conceptus regulates the deciduali-zation process in the baboon. Buy Asthma Inhalers Online
The objective of this study was to define appropriate in vitro culture conditions to mimic changes associated with stromal cell decidualization in vivo in a nonhuman primate model. Specifically, aSMA and IGFBP-1 were measured as markers for decidualizing stromal cells after treatment with estradiol-17p, medroxyprogesterone acetate (MPA), and re-laxin in the presence or absence of the cAMP analogue, N6,2′-0-dibutyryl cAMP (dbcAMP). Furthermore, a comparison of the regulatory transcripts of the protein kinase A (PKA) subunits—RIa, RIp, RIIa, and RIIp—between decidualized and nondecidualized cells was done in order to investigate a potential mechanism of cAMP action during the decidualization process. Parallel studies with human endometrial stromal cells were done strictly for comparative analysis. Our studies suggest that while hormones alone are sufficient to decidualize human stromal cells in vitro, dbcAMP in conjunction with hormones is required for induction of this transformation in baboon stromal fibroblasts.