Carson G D, Bolla J D, Challis J R
Endocrinology. 1979 Apr;104(4):1053-8. doi: 10.1210/endo-104-4-1053.
This study examined whether cortisol, present in amniotic fluid (AF), could reach the fetal blood, and might be available to various fetal organs and to the fetal membranes and placenta. [3H]Cortisol ([3H]F) was injected into the AF of five sheep at 130--143 days gestation. Samples of AF and fetal blood were collected for 120 min, at which time the fetuses were delivered and fetal organs and fluid were collected for measurement of the [3H]F content. [3H]F disappeared from AF with an initial half-life of about 40 min and was detected in fetal blood by 30 min after intraamniotic injection. At 120 min after injection, [3H]F was widely distributed within the pregnant uterus, and the highest concentrations of radioactivity were found in allantoic fluid, fetal membranes, and placental tissue. The concentration of [3H]F in the umbilical vein was higher than in umbilical arterial blood in four of five sheep. [3H]F and [3H]cortisone were found in several fetal tissues, including adrenal, kidney, pancreas, lung, and liver. [3H]F in tracheal and stomach fluid was generally less than in fetal blood. We conclude that 1) cortisol can reach the fetus from AF, 2) a major route of entry may be via the vasculature of the fetal membranes, 3) a considerable proportion of [3H]F is retained by the fetal membranes, and 4) interconversion of [3H]F and [3H]cortisone may occur in some fetal tissues.
本研究检测了羊水中存在的皮质醇是否能进入胎儿血液，以及是否能到达胎儿的各个器官、胎膜和胎盘。在妊娠130 - 143天，向5只绵羊的羊膜腔内注射了[³H]皮质醇（[³H]F）。采集羊水和胎儿血液样本120分钟，之后娩出胎儿，收集胎儿器官和液体以测量[³H]F含量。[³H]F从羊水中消失的初始半衰期约为40分钟，羊膜腔内注射后30分钟在胎儿血液中检测到。注射后120分钟，[³H]F广泛分布于妊娠子宫内，放射性最高浓度见于尿囊液、胎膜和胎盘组织。5只绵羊中有4只脐静脉中[³H]F的浓度高于脐动脉血。在包括肾上腺、肾脏、胰腺、肺和肝脏在内的几种胎儿组织中发现了[³H]F和[³H]可的松。气管和胃内液体中的[³H]F通常低于胎儿血液中的浓度。我们得出以下结论：1）皮质醇可从羊水进入胎儿体内；2）主要进入途径可能是通过胎膜的血管系统；3）相当一部分[³H]F被胎膜保留；4）[³H]F和[³H]可的松在某些胎儿组织中可能会相互转化。
