All of the following take part in the pathogenesis of macular edema in diabetic retinopathy except –

Etiopathogenis of diabetic retinopathy (including macular edema) Following factors are important in development of diabetic microangiopathy, which is responsible for the development of retinopathy :- Activation of protein kinase C Oxidative stress Increased production of growth factors, amongst which Vascular endothelial growth factor A (VEGF-A is the most important). Other factors are TGF - β, PDGF, EGF and IGF