VASCULAR-PERMEABILITY FACTOR ACCELERATES ENDOTHELIAL REGROWTH FOLLOWING BALLOON ANGIOPLASTY

Many failures of vascular reconstructions are due to thrombosis and re stenosis and are often attributed to inadequate endothelial regenerati on at the site of endothelial denudation. Vascular permeability factor (VPF) is a naturally occurring growth factor responsible for vessel p ermeability and microvascular angiogenesis. Here, we show that VPF sti mulated rabbit endothelial cell proliferation in vitro at concentratio ns 100 ng/ml. However, VPF had no effect on smooth muscle cell prolife ration at these concentrations up to 500 ng/ml. When VPF was administe red for 4 weeks (120 mu g, twice weekly, i.v.) following balloon angio plasty-induced endothelial denudation of rabbit carotid artery, there was a significant increase in the in vivo regeneration of endothelium compared to control (57.5 +/- 6.7% vs. 38.3 +/- 1.9%, P < 0.01). Moreo ver, 8 weeks of VPF administration resulted in 88.1 +/- 3.1% re-endoth elialization compared to control (44.7 +/- 3.8%). Hence, VPF appears t o be a specific mitogen for endothelial regeneration.