Burton G J, Reshetnikova O S, Milovanov A P, Teleshova O V
Department of Anatomy, University of Cambridge, UK.
Placenta. 1996 Jan;17(1):49-55. doi: 10.1016/s0143-4004(05)80643-5.
The aim was to determine whether the fetal vasculature of the human placenta adapts in a uniform manner to different forms of hypoxic stress. Stereological analyses were performed on the intermediate and terminal villi of placentae obtained from each of the following conditions; high altitude (up to 2800 m), maternal iron-deficiency anaemia and pre-eclampsia. These conditions were taken to represent hypoxic, anaemic and ischaemic hypoxia, respectively. In each situation, there was a trend for the volume fraction of the fetal capillaries to be higher than in the controls, although the differences were statistically significant only for the cases of hypoxic and anaemia hypoxia. This was due, in part, to capillaries being of larger diameter. Evidence for capillary proliferation was inconsistent. At high altitude there was a trend for the capillary length density to be raised, but there was no change in the ratio of capillary:villous length. In both maternal anaemia and pre-eclampsia the capillary length density remained constant, but the ratio of capillary:villous length was significantly raised in the former. These results suggest that dilatation of the capillary sinusoids, with accompanying thinning of the villous membrane, is the principal adaptation to hypoxia under the conditions studied.
目的是确定人类胎盘的胎儿血管系统是否以统一的方式适应不同形式的缺氧应激。对从以下每种情况获得的胎盘的中间绒毛和终末绒毛进行体视学分析：高海拔（高达2800米）、母体缺铁性贫血和子痫前期。这些情况分别被视为代表低氧、贫血性和缺血性缺氧。在每种情况下，胎儿毛细血管的体积分数都有高于对照组的趋势，尽管差异仅在低氧和贫血性缺氧病例中具有统计学意义。这部分是由于毛细血管直径较大。毛细血管增殖的证据并不一致。在高海拔地区，毛细血管长度密度有升高的趋势，但毛细血管与绒毛长度的比值没有变化。在母体贫血和子痫前期中，毛细血管长度密度保持不变，但在前者中毛细血管与绒毛长度的比值显著升高。这些结果表明，在所研究的条件下，毛细血管血窦扩张并伴有绒毛膜变薄是对缺氧的主要适应性变化。
