VEGFA and ischemia: Results from this model strongly suggested that the loss of pericyte is spatially and temporally associated with the development of histopathologic lesions characteristic of retinopathy, including formation of microaneurysms, degenerative capillaries, and increased vascular permeability.38 Since formation of acellular capillaries results in capillary nonperfusion, due to ischemia, VEGF expression is increased, resulting in neovascularization.