The Presence of VEGF Receptors on the Luminal Surface of Endothelial Cells Affects VEGF Distribution and VEGF Signaling
Figure 6
Flow diagrams for a total receptor density of 10,000 per endothelial cells.
A. The density of total (luminal and abluminal) receptors per endothelial cell is fixed at 10,000 (VEGFR1∶VEGFR2∶NRP1 expression is 1∶1∶1). Scenario (a): all the receptors are located on the endothelial abluminal surface (yellow circle on Figure 4A); scenario (b): the receptors are evenly distributed between the luminal and abluminal endothelial surface (purple circle on Figure 4A); scenario (c): all the receptors are located on the endothelial luminal surface. Numbers represent absolute values of VEGF flows expressed in pmoles/s. Percentages of VEGF secretion in parentheses. B. Generalization of particular cases shown in A. The density of receptors varies between 0 and 10,000 receptors per endothelial cell surface. The total receptor density is fixed at 10,000 receptors per endothelial cell. Left: absolute values; Right: percentages of VEGF secretion.