Ets1−/−;Ets2A72/A72 mutant embryos have edema and hemorrhage, but blood vessel structure is unaffected. (A) E11.5 (top) and E14.5 (bottom) embryos; control embryo is at the left, mutant embryo is at the right. Boxed areas are enlarged to show region of edema at E11.5 or hemorrhage at E14.5. Bars, 0.5 mm. (B) Cryosections of control (top) and Ets1−/−;Ets2 A72/A72 (bottom) embryos were stained with anti–PECAM antibody (green) and anti–smooth muscle α-actin antibody (red). Representative data for E13.5 embryo are shown; a total of 4 embryos were analyzed. Bars, 50 μm