Expression of Foxm1 Transcription Factor in Cardiomyocytes Is Required for Myocardial Development
Figure 5
Decreased capillary density and cardiac fibrosis in Nkx2.5-Cre/Foxm1fl/fl heart.
Microtome sections of paraffin-embedded hearts were prepared from either Nkx2.5-Cre/Foxm1fl/fl or littermate control mice at P11 and stained for PECAM-1 (A–B), α-smooth muscle actin (αSM) (C–D) or Masson's Trichrome (E–H). Capillary density was decreased in Nkx2.5-Cre/Foxm1fl/fl hearts at P11 (A–B, I), while coronary vessel formation was not altered (C–D). Numbers of capillaries were counted in PECAM-stained hearts using 10 random sections and mean±SEM was determined to confirm decreased capillary density (I). Significant fibrosis was detected in the IVS and ventricular walls of Nkx2.5-Cre/Foxm1fl/fl hearts (F, H) while none was detected in control hearts (E, G). Significant differences (p<0.05) were indicated by asterisk. Scale bars represent 100 µm in A–F and 50 µm in G–H.