Figure 4. AV cushion development and cardiac cell proliferation in BMPRIIflox/−;Mox2-Cre mice.
Cardiac tissues from control (A, C, E, G) and mutant (B, D, F, H) are shown. (A, B) Sections of the AV cushion at E11.5 were stained with hematoxylin and eosin. (C, D) Sections shown in A and B were reacted with antibody directed against phosphorylated Smads1, 5, and 8 (green) and counterstained with propidium idodide (red). (E, F) Immunohistostaining for NFATc1 (brown) at E9.5 is shown. AVC: AV cushion. (G, H) BrdU incorporation for 4 hours was performed to detect proliferating cardiac cells (brown nuclei) at E16.5. Scale bars: 0.1 mm (A–F) and 0.5 mm (G, H).