Schneider-Kolsky M E, Manuelpillai U, Waldron K, Dole A, Wallace E M
Centre for Women's Health Research, Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia.
Placenta. 2002 Apr;23(4):294-302. doi: 10.1053/plac.2002.0787.
The aim of this study was to investigate localization and content of activin beta A-subunit and activin receptors in gestational tissues throughout pregnancy and in association with term labour. Placenta and fetal membranes were collected from women undergoing first and second trimester terminations and from women before and after term labour. Activin beta A-subunit and activin receptors IA, IB, IIA and IIB were studied by immunohistochemistry. Term tissues were analysed for activin A and follistatin content by ELISA and the presence of receptor proteins was assessed by Western hybridization. Activin beta A-subunit was localized to the syncytiotrophoblast and cytotrophoblast in placentae from all gestational ages, and to the amniotic epithelial and chorionic trophoblast layer at term. In placentae of first and second trimester, receptor proteins were localized to the syncytium, whereas at term, the distribution was confined predominantly to vascular endothelial cells of villous blood vessels. Receptor proteins in amnion were localized to some epithelial cells, mesenchyme and chorionic trophoblast. These findings suggest that activin A is secreted by and targets the placental syncytium and amniotic epithelium in early pregnancy, but at term targets the vascular endothelium of placenta and the fetal membranes. There were no differences with labour onset.
本研究的目的是调查激活素βA亚基和激活素受体在整个孕期的妊娠组织中的定位和含量，以及与足月分娩的关系。从接受孕早期和孕中期终止妊娠的妇女以及足月分娩前后的妇女中收集胎盘和胎膜。通过免疫组织化学研究激活素βA亚基和激活素受体IA、IB、IIA和IIB。通过酶联免疫吸附测定法（ELISA）分析足月组织中的激活素A和卵泡抑素含量，并通过蛋白质印迹法评估受体蛋白的存在情况。激活素βA亚基在所有孕周胎盘的合体滋养层和细胞滋养层中均有定位，足月时在羊膜上皮和绒毛膜滋养层中也有定位。在孕早期和孕中期的胎盘中，受体蛋白定位于合体细胞，而在足月时，其分布主要局限于绒毛血管的血管内皮细胞。羊膜中的受体蛋白定位于一些上皮细胞、间充质和绒毛膜滋养层。这些发现表明，激活素A在妊娠早期由胎盘合体细胞和羊膜上皮分泌并作用于这些细胞，但在足月时作用于胎盘和胎膜的血管内皮。分娩发动前后无差异。
