Figure 3
Hearts in mutant embryos are smaller and dysmorphic. Photomicrographs (40×) of transverse sections of mouse embryos at E12.5 (A, B) and E13.5 (C, D) stained with hematoxylin and eosin. Tie2Cre+/-Srff/fembryos exhibited reduced heart size by E12.5 (B, compare to A), which became more pronounced and consistent at E13.5 (D, compare to C). (E) Quantitation of heart size normalized to overall body weight revealed smaller hearts in both E12.5 (1.5 ± 0.4 vs. 1.08 ± 0.5, wild-type vs. mutant respectively; p = 0.054) and E13.5 embryos (1.4 ± 0.39% vs. 1.04 ± 0.17%, wild-type vs. mutant respectively; p = 0.021). Enlarged vessels apparently caused by edema due to vascular insufficiency were also noted in mutant embryos (asterisks). LV = left ventricle. Scale bar: 200 μm.