Superoxide dismutases in retinal degeneration of WBN/Kob rat.

Purpose. To examine the relationship between retinal degeneration and superoxide dismutase (SOD) in the degenerative retina of the WBN/Kob rat. Methods. The retinas of 4-week-old and 10-month-old WBN/Kob rats were examined with immunohistochemistry and immunoblotting. Wistar Kyoto rats were used as controls. Results. Retinal degeneration began 4 weeks after birth. Four-week-old WBN/Kob rats showed no manganese superoxide dismutase (Mn-SOD) immunoreactivity in the photoreceptor inner segments or copper-zinc superoxide dismutase (CuZn-SOD) immunoreactivity in the outer nuclear layer or photoreceptor inner segments. Control 4-week-old Wistar Kyoto rats showed positive immunoreactivities at these sites. Conclusions. The retinal degeneration of WBN/Kob rats begins in the outer retina. The lack of SODs in the outer retina may contribute to retinal degeneration in the WBN/Kob rats.