Likewise, the inhibition of inflammation has been shown to preserve the retinal vasculature despite hyperglycaemia [46, 59–61], and deletion or inhibition of certain inflammatory proteins or cytokines such as ICAM1, inducible nitric oxide synthase (iNOS) and IL1β inhibited diabetes-induced degeneration of retinal capillaries in diabetic animals [62–64]. Here, NOS2 is linked to diabetes mellitus.