James Joanna L, Stone P R, Chamley L W
Department of Obstetrics and Gynecology, University of Auckland, Auckland, New Zealand.
Hum Reprod. 2006 Oct;21(10):2699-705. doi: 10.1093/humrep/del212. Epub 2006 Jun 28.
In the first trimester of human pregnancy, extravillous trophoblasts from placental villi invade the decidua temporarily occluding the spiral arteries, preventing maternal blood flow and creating a low-oxygen environment, which is believed to play an important role in the regulation of extravillous trophoblast outgrowth. This work aimed to quantify the effects of gestational age and oxygen concentration on extravillous trophoblast outgrowth.
A quantitative first trimester villous explant model was used to measure the frequency and area of extravillous trophoblast outgrowths from villi grown in 1.5 or 8% oxygen.
The percentage of explants producing outgrowth declined independently of oxygen concentration as gestation increased from 8 to 12 weeks. Culture in 1.5% oxygen significantly reduced the frequency and area of outgrowths in comparison with 8% oxygen. HLA-G and alpha1 integrin were both expressed throughout outgrowths, with no difference in the expression between oxygen concentrations. Gestation influenced the response of explants to oxygen, with a significant differential response to oxygen concentration in placentae under 11 weeks of gestation, whereas in villi from placentae of 11 or 12 weeks, no differential response was observed.
In the first trimester, oxygen and gestational age both regulate extravillous trophoblast outgrowth.
在人类妊娠的头三个月，胎盘绒毛的绒毛外滋养层侵入蜕膜，暂时阻塞螺旋动脉，阻止母体血流并创造低氧环境，这被认为在绒毛外滋养层生长的调节中起重要作用。这项工作旨在量化胎龄和氧浓度对绒毛外滋养层生长的影响。
使用定量的头三个月绒毛外植体模型来测量在1.5%或8%氧气中生长的绒毛的绒毛外滋养层生长的频率和面积。
随着孕周从8周增加到12周，产生生长的外植体百分比与氧浓度无关而下降。与8%氧气相比，在1.5%氧气中培养显著降低了生长的频率和面积。HLA - G和α1整合素在整个生长过程中均有表达，氧浓度之间的表达无差异。孕周影响外植体对氧气的反应，在妊娠11周以下的胎盘中，对氧浓度有显著的差异反应，而在11或12周胎盘的绒毛中，未观察到差异反应。
在头三个月，氧气和孕周均调节绒毛外滋养层的生长。
