Campbell W J, Deb S, Kwok S C, Joslin J A, Soares M J
Department of Physiology, Ralph L. Smith, Mental Retardation Research Center, University of Kansas Medical Center, Kansas City 66103.
Endocrinology. 1989 Sep;125(3):1565-74. doi: 10.1210/endo-125-3-1565.
The rat chorioallantoic placenta is comprised of two morphologically distinct regions: the junctional zone and the labyrinth zone. The purpose of this investigation was to determine the relative contributions of trophoblast cells in each of these regions to the expression of placental lactogen-II (PL-II) and PRL-like protein-A (PLP-A) during development, mRNA expression was estimated by Northern blot analysis, whereas, protein expression was estimated by electrophoresis, immunoblotting, and immunocytochemical analyses. The immunochemical analyses used antipeptide antisera directed to amino acids 56-70 of PL-II and amino acids 152-164 of PLP-A. Northern and immunoblotting analyses indicated that both PL-II mRNA and protein expression were maximal in the junctional zone on day 13 of gestation and declined as gestation proceeded. In contrast, PL-II mRNA and protein expression in the labyrinth zone were low on day 13 and increased as gestation advanced. PL-II was specifically localized to giant cells. At midgestation, PL-II-positive giant cells were identified bordering the uterine decidua in the junctional zone and choriovitelline placenta. As gestation advanced. PL-II-positive cells were also localized to the labyrinth zone. Immunoreactivity was restricted to the cytoplasm of PL-II-positive cells. PLP-A mRNA and protein were predominantly expressed in the junctional zone of the chorioallantoic placenta. Expression of PLP-A increased as gestation advanced. PLP-A was specifically localized to giant and spongiotrophoblast cells of the junctional zone. Immunoreactivity was found in both cytoplasmic and nuclear compartments of PLP-A-positive cells. In summary, PL-II expression shifts from the junctional to the labyrinth zone during pregnancy, whereas PLP-A is predominantly expressed in the junctional zone during the latter third of pregnancy. Both hormones are produced by giant cells of the junctional zone, but only PL-II is expressed by choriovitelline and labyrinthine trophoblast cells. PLP-A is also expressed by spongiotrophoblast cells of the junctional zone. These findings provide insights into the process of placental morphogenesis.
连接区和迷路区。本研究的目的是确定这些区域中滋养层细胞在发育过程中对胎盘催乳素-II（PL-II）和催乳素样蛋白-A（PLP-A）表达的相对贡献，通过Northern印迹分析估计mRNA表达，而通过电泳、免疫印迹和免疫细胞化学分析估计蛋白质表达。免疫化学分析使用针对PL-II的56-70位氨基酸和PLP-A的152-164位氨基酸的抗肽抗血清。Northern印迹和免疫印迹分析表明，PL-II mRNA和蛋白质表达在妊娠第13天的连接区最高，并随着妊娠进展而下降。相反，迷路区的PL-II mRNA和蛋白质表达在第13天较低，并随着妊娠进展而增加。PL-II特异性定位于巨细胞。在妊娠中期，在连接区和绒毛膜卵黄囊胎盘的子宫蜕膜边界处鉴定出PL-II阳性巨细胞。随着妊娠进展，PL-II阳性细胞也定位于迷路区。免疫反应性局限于PL-II阳性细胞的细胞质。PLP-A mRNA和蛋白质主要在绒毛膜尿囊胎盘的连接区表达。随着妊娠进展，PLP-A的表达增加。PLP-A特异性定位于连接区的巨细胞和海绵滋养层细胞。在PLP-A阳性细胞的细胞质和细胞核中均发现免疫反应性。总之，PL-II表达在妊娠期间从连接区转移到迷路区，而PLP-A在妊娠后期主要在连接区表达。两种激素均由连接区的巨细胞产生，但只有PL-II由绒毛膜卵黄囊和迷路滋养层细胞表达。PLP-A也由连接区的海绵滋养层细胞表达。这些发现为胎盘形态发生过程提供了见解。
