Lee R, Mayhew T M
Department of Human Morphology, University of Nottingham, UK.
J Anat. 1995 Apr;186 ( Pt 2)(Pt 2):349-55.
Histological sections of placentae from pregnancies completed at low altitude (400 m) and high altitude (3600 m) in Bolivia were analysed using a stereological estimator of the star volumes of villous 'domains' and intervillous 'pores'. The purpose was to test whether or not differences in the overall volumes of these compartments are accompanied by changes in their geometrical relationships. Whilst total placental volume did not vary with altitude, the total volume of villi declined by about 25% and total intervillous volume increased by 40% at high altitude. The star volume of villi also decreased by 25% (from 1.5 x 10(6) microns 3 at low altitude to 1.1 x 10(6) microns 3 at high altitude) whilst the star volume of intervillous pores increased 4-fold (from 87 x 10(6) microns 3 to 461 x 10(6) microns 3). These figures imply that villous domains decrease in size but may be constant in number. The most likely explanation is that villous trees at high altitude are scaled-down versions of their low-altitude counterparts. By contrast, although the intervillous pores enlarge they may decrease in number in the highland organ. This may reflect a change in the number of maternal cotyledons or in the spatial arrangement of villous trees.
对玻利维亚低海拔（400米）和高海拔（3600米）地区足月妊娠胎盘的组织切片，使用体视学方法估计绒毛“区域”和绒毛间隙“孔隙”的星体积进行分析。目的是检验这些腔室总体积的差异是否伴随着其几何关系的变化。虽然胎盘总体积不随海拔高度变化，但在高海拔地区绒毛总体积下降约25%，绒毛间隙总体积增加40%。绒毛的星体积也下降了25%（从低海拔的1.5×10⁶立方微米降至高海拔的1.1×10⁶立方微米），而绒毛间隙孔隙的星体积增加了4倍（从87×10⁶立方微米增至461×10⁶立方微米）。这些数据表明绒毛区域尺寸减小但数量可能不变。最可能的解释是高海拔地区的绒毛树是低海拔地区绒毛树的缩小版本。相比之下，虽然绒毛间隙孔隙增大，但在高海拔器官中其数量可能减少。这可能反映了母体小叶数量的变化或绒毛树空间排列的变化。
