Morphology of the growing sprouts with endothelial cell proliferation dependent VEGF concentration.

<p>In plate A we indicate the morphology of the growing sprout (by using different colours) for different values of maximum proliferation (<i>M</i>_<i>P</i>) and limit VEGF concentration (<i>L</i>_<i>V</i>). In these simulation the proliferation rate increases linearly with the VEGF concentration until it reaches the value <i>M</i>_<i>P</i> at the VEGF concentration <i>L</i>_<i>V</i>. The colours indicate the morphology of the observed sprouts for the corresponding parameters: blue dots correspond to situations where the sprout breaks, the green dots correspond to well formed sprouts without appreciable thickening of the parental vessel, the orange dots correspond to well formed sprouts with appreciable thickening of the parental vessel, and the red dots correspond to deformed vessels (triangular sprouts in this case). We observe that the sprout breaks for low proliferation rates, but there is a large region of the parameter space with well formed sprouts. There is however extensive parental vessel thickening. In plates B1, B2, B3 and B4 we plot examples of the morphologies observed (the color of the border in these plates follows the same code as in plate A). The parameters used to obtain the morphologies depicted in B1, B2, B3 and B4 are indicated by arrows in plate A.