Role of vascular endothelial growth factor and vascular endothelial growth factor receptors in vascular development.

Abstract

Distinct cellular processes mediate blood-vessel formation during embryogenesis (Beck and D’Amore 1997; Carmeliet and Collen 1998a; Folkman and D’Amore 1996; Noden 1989; Risau 1997; Wilting and Christ 1996) (Fig. 1). Initially, mesodermal cells differentiate in situ into early haemangioblasts and form cellular aggregates (blood islands), in which the inner-cell population develops into haematopoietic precursors and the outer-cell population gives rise to the primitive endothelial cells. In vitro findings suggest that basic fibroblast growth factor (bFGF or FGF2) may participate in angioblast differentiation via induction of a cellular receptor for vascular endothelial growth factor (VEGF-A) (Flamme and Risau 1992).