Oxidative-nitrosative stress, manifest in increased lipid peroxidation, accumulation of nitrated and poly(ADP-ribosyl)ated proteins, excessive superoxide production, and downregulation of several antioxidative defense enzymes i.e., superoxide dismutase, glutathione peroxidase, and glutathione reductase, is present in the rat retina early after induction of STZ-diabetes (14,37,59–62). The gene discussed is GSR; the disease is diabetes mellitus.