Ontogeny of copper-zinc and manganese superoxide dismutase in the developing rat retina: immunohistochemical and immunochemical study.

The localization of copper-zinc and manganese superoxide dismutase (SOD) in the developing rat retina was studied immunohistochemically and immunochemically. Immunoreactivity to Cu/Zn SOD was observed in the inner limiting membrane, nerve fiber layer, ganglion cell layer (GCL) and pigment epithelium on postnatal day (P) 7. From P7 to at least 10 weeks, the distribution of Cu/Zn SOD remained unchanged in rats. From P15 to P30, the immunoreactivity to Mn SOD appeared in the GCL and inner plexiform layer. The distribution of Mn SOD remained unchanged between P30 and 10 weeks. Our immunochemical study revealed that the concentration of Cu/Zn SOD was higher than that of Mn SOD throughout the postnatal period. The differential distributions of Cu/Zn SOD in the developing rat retina support the hypothesis that Cu/Zn and Mn SOD play an important role in the protection against oxygen free radicals in the different layers of the retina throughout development.