Power S G, Patrick J E, Carson G D, Challis J R
Endocrinology. 1982 Feb;110(2):481-6. doi: 10.1210/endo-110-2-481.
To assess the possible source of progesterone in the fetal fluids of pregnant sheep, we measured the changes in progesterone concentrations in amniotic fluid (AF) and allantoic fluid (ALF) during pregnancy and compared these values with those in the maternal and fetal circulations. In acute experiments, the concentration of progesterone in ALF was greater than that in AF, and in both compartments, progesterone rose progressively between day 50 of pregnancy and term (day 145). In contrast, in maternal peripheral and uterine venous blood as well as in umbilical cord blood the mean concentration of progesterone increased until day 130, but fell at term. Similar results were obtained in chronically catheterized sheep during late pregnancy. The pattern of progesterone change in the AF and ALF suggested that the steroid might originate from a different source than progesterone in the vascular compartments. By means of in vitro incubation studies, we showed that the chorioallantoic membrane and amnion from sheep at term pregnancy had the capacity to convert [3H]pregnenolone to [3H]progesterone. These results raise the possibility that there may be local changes in steroid hormone concentrations within the tissues and fluids of the pregnant uterus. These changes could be of importance in altering the intrauterine endocrine milieu at the time of birth.
为评估孕羊胎儿体液中孕酮的可能来源，我们测定了孕期羊水（AF）和尿囊液（ALF）中孕酮浓度的变化，并将这些值与母体和胎儿循环中的值进行比较。在急性实验中，ALF中孕酮的浓度高于AF，且在这两个腔室中，孕酮在妊娠第50天至足月（第145天）期间逐渐升高。相比之下，在母体外周血、子宫静脉血以及脐带血中，孕酮的平均浓度在第130天之前升高，但在足月时下降。在妊娠后期长期插管的绵羊中也获得了类似的结果。AF和ALF中孕酮的变化模式表明，该类固醇的来源可能与血管腔室中的孕酮不同。通过体外孵育研究，我们表明足月妊娠绵羊的绒毛尿囊膜和羊膜有能力将[3H]孕烯醇酮转化为[3H]孕酮。这些结果增加了一种可能性，即妊娠子宫的组织和体液中可能存在类固醇激素浓度的局部变化。这些变化可能对出生时改变子宫内的内分泌环境具有重要意义。
