EXPRESSION OF VASCULAR-PERMEABILITY FACTOR (VPF VEGF) IS ALTERED IN MANY GLOMERULAR-DISEASES/

Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), is a potent enhancer of microvascular permeabil ity and a selective endothelial cell growth factor, In normal human ki dney, VPF/VEGF mRNA and protein are strongly expressed by visceral glo merular epithelial cells, and VPF/VEGF may be an important regulator o f glomerular endothelial cell function. This study examined 47 renal b iopsies from patients with a variety of glomerular diseases for expres sion of VPF/VEGF mRNA and protein by in situ hybridization and immunoh istochemistry, In many glomerular diseases, VPF/VEGF-expressing cells were decreased in number or absent in areas of focal or global glomeru lar sclerosis, Decreased numbers of VPF/VEGF-expressing cells in glome ruli were also noted in amyloidosis, diabetes, crescentic glomerulonep hritis, and diffuse endocapillary proliferative glomerulonephritis ass ociated with systemic lupus erythematosus. Normally, release of VPF/VE GF must be under strict control because it is some 50,000 times more p otent than histamine as an inducer of microvascular permeability. Dama ge to visceral epithelial cells in a variety of glomerular diseases ha s the potential for releasing relatively large amounts of VPF/VEGF loc ally, leading to increased glomerular permeability. In addition, becau se VPF/VEGF is also an endothelial growth factor, the loss of normal, controlled secretion of VPF/VEGF after damage to visceral epithelial c ells could lead to important alterations in glomerular endothelial cel l function.