Vascular endothelial growth factor (VEGF) is a highly specific mitogen for vascular endothelial cells. Five VEGF isoforms are generated as a result of alternative splicing from a single VEGF gene. These isoforms differ in their molecular mass and in biological properties such as their ability to bind to cell-surface heparan-sulfate proteoglycans. Mouse VEGF120 shares 98% aa sequence identity with corresponding regions of rat, 89% with canine, feline, equine and porcine, and 87% with human, ovine and bovine VEGF, respectively. VEGF120 and VEGF164, for inducing leukocyte stasis (leukostasis) within the retinal vasculature and blood-retinal barrier (BRB) breakdown and to determine whether endogenous VEGF164 mediates retinal leukostasis.