ERYTHROCYTE CATALASE AND DETOXICATION OF HYDROGEN PEROXIDE

Erythrocytes from several animal species with widely differing catalase levels were exposed to H 2 O 2 and the susceptibility of Hb to oxidation measured. In the absence of glucose the rapidity of MHb formation was inversely related to the catalase activity and directly related to the concentration of H 2 O 2 attained. Added catalase or hemolysates of catalase-rich erythrocytes counteracted the effect of H 2 O 2 , while azide rendered Hb of even catalase-rich cells susceptible to rapid oxidation. Added glucose largely prevented the formation of MHb on exposure to H 2 O 2 ; this protective effect was less marked in azide-treated cells than in control cells. These results suggest that catalase complements the protective action of glucose and thereby regulates MHb formation and accumulation in erythrocytes.