Regulation of Microvascular Permeability by Vascular Endothelial Growth Factors

The study explored the role of vascular endothelial growth factors (VEGFs) in regulating microvascular permeability, particularly during angiogenesis. Angiogenesis, the formation of new blood vessels, was associated with increased vascular permeability, more pronounced in pathological conditions such as cancer, diabetes, and heart disease. VEGFs acted on specific receptors (VEGF-R1 and VEGF-R2) to promote vessel growth and increase permeability to water and proteins. The research demonstrated that in anesthetized frogs, VEGFs increased permeability in mesenteric microvessels by activating a signaling pathway involving tyrosine autophosphorylation, phospholipase C, and calcium influx. This led to the formation of various pathways through endothelial cells, although the exact mechanism in vivo remained unclear.