Figure 5. Antioxidant effects of OTC in the Ccl2^−/−/Cx3cr1^−/− double knockout mouse retina. Intracellular concentrations of glutathione (GSH) were measured in (A) sera and (B) samples of the neural retina (NR) and retinal pigment epithelium (RPE) and eyecup obtained from double knockout (DKO rd8) mice treated with L-2-oxothiazolidine-4-carboxylic acid (OTC DKO rd8) or regular drinking water (Con OTC DKO rd8) for a period of 5 months. (C) Superoxide generation was also assessed in these animals with the fluorescent indicator dihydroethidium (DHE). *p<0.01 compared to corresponding Con DKO rd8 NR or RPE; **p<0.01 compared to Con DKO rd8 NR.