Studies on the maternal control of pregnancy-stage specific function of the placenta

胎盘在妊娠期间对胎儿生长/存活和维持母体黄体功能起着至关重要的作用。胎盘的功能表现出妊娠阶段特异性的方式，即包括胎盘催乳素（PL）在内的胎盘激素的分泌模式在妊娠过程中表现出特定的变化。我们成功地分离出一个新的孕中期特异性PL的cDNA克隆。这种新的PL，PL-m，在第10天和第12天特异性表达，并具有可能的N-糖基化位点。妊娠中期特异性PL包括PL-Im和PL-I，如果妊娠期延长，则在妊娠晚期再次分泌。PL的第二次分泌完全取决于源自卵巢的因素，要么通过连续用PMSG和hCG处理诱导一组新的黄体，要么植入黄体酮。我们还鉴定了几种胎盘糖缀合物，包括糖蛋白和糖脂，其表达妊娠阶段特异性方式。糖蛋白也在这些延长妊娠模型中重新出现。我们的研究结果表明，卵巢参与胎盘功能的控制机制，提供了一个概念，即从卵巢到胎盘的信息流存在控制胎盘功能。

The placenta plays an essential role in fetal growth/survival and the maintenance of maternal luteal function during pregnancy. The function of placenta expresses pregnancy-stage specific manner ; i.e.the secretory profiles of placental hormones including placental lactogens (PLs) show specific changes during the course of pregnancy. We succeeded to isolate a clone of the cDNA for a novel mid-pregnancy specific PL.This novel PL, PL-m, is expressed specifically on days 10 and 12, and has possible N-glycosylation sites. The mid-pregnancy-specific PLs including, PL-Im and PL-I, are secreted again during late pregnancy if the period of pregnancy is extended. This second secretion of PLs depends entirely on factors originating from the ovary, either by induction of a new set of corpora lutea by successive treatment with PMSG and hCG or implantation of progesterone. We also identified several placental glycoconjugates including glycoproteins and glycolipids which expresses pregnancy-stage specific manner. The glycoproteins also reappear in these prolonged pregnancy model. The results of our investigation indicate that the ovary is involved in the control mechanism of placental function, providing the concept that an information flow from the ovary to the placenta exists to control placental function.