HIF1A and endothelial dysfunction: For example, in an ocular ischemia/reperfusion model in pigs where an ischemic period of 12 min was followed by 20 h of reperfusion, RGC loss, endothelial dysfunction and oxidative stress in retinal arterioles were observed together with upregulation of HIF-1α, VEGF-A, and NOX2 [307].