Figure 5. Effects of endometrial VEGF overexpression on placentas of surviving pregnancies that did not exhibit severe vascular changes.

(A–H) Trophoblast-lined SpAs at the JZ (A–D) and endothelium-lined SpAs in deeper decidua, 300 μm below the JZ (E–H). There were no marked changes between control and Endo-VEGF animals in either trophoblast-invaded (CK8-positive; arrowheads) SpAs (B and D) or endothelium-lined SpAs (F and H). (I–L) Expansion of the JZ, specifically GlyTCs (arrowheads), and dilation of venous channels (arrows) in Endo-VEGF animals (K and L) compared with controls (I and J). (M–P) Upon VEGF overexpression, there were no changes in SpA and central canal diameter (M), but significant increases were observed in cross-sectional area and diameter of venous channels (N) and in total JZ and GlyTC areas (O). (P) The depth of trophoblast invasion into the decidua was not significantly changed between groups. Sp, spongiotrophoblast. Results are mean ± SD. *P < 0.05 (n = 15). Scale bars: 50 μm (A–H); 100 μm (I and K); 20 μm (J and L).