Figure 11.

Flow alters outflow tract explant cell death and proliferation. Transmission Electron Microscopy was performed to investigate subcellular architecture. All samples contained myocyte cells as indicated by the presence of sarcomeres (arrowheads) and centrally located nuclei (A) Samples subjected to physiological flow exhibited an endothelial layer lining the flow side of the cushion, as well as ECM deposition and membranous protrusions (arrow). (B) Physiological no flow controls had some dead cell debris beneath the luminal cell layer. (C) Pathological flow groups did not show a luminal endothelial layer but showed MCs surrounded by ECM and cell debris. (D) Pathological no flow controls were similar to physiological no flow controls. Scale bars are all 200 μm. (E) Confocal microscopy was performed on sample groups for P-Histone H3 as a proliferative marker. P-Histone H3 (+) nuclei relative to total nuclei (Dapi) were quantified and indicated increase proliferation in the case of pathological flow. (^*P < 0.05).