Effects of intravenous superoxide dismutase and catalase on electroretinogram in the cat postischemic retina.

We examined the effects of the antioxidant enzymes, 10,000 U/kg of superoxide dismutase (SOD) and 50,000 U/kg of catalase (CAT) on cat electroretinograms during the reperfusion after retinal ischemia. The intravenous administrations of SOD and CAT promoted the recovery of the c-wave after 30 min of ischemia but not the b-wave. At 5 min after onset of reperfusion, SOD- and CAT-treated eyes showed 90 and 110% recovery of the c-wave amplitude respectively, against 50% recovery in the untreated eyes. These results suggested that the oxygen-derived free radicals affected the retinal pigment epithelium at the early period of reperfusion.