Studies on cysteine-induced hemolysis.

Two mechanisms of cysteine-induced lysis of washed rat erythrocytes appear to exist; one operating at low, the other at somewhat higher cysteine concentration. DETAPAC (20 microM) and EDTA (0.1 mM) markedly reduced the effect of the latter mechanism. Copper and iron ions, ascorbate, dehydroascorbate and glucose protected the erythrocytes against cysteine-induced hemolysis, while superoxide dismutase, catalase, hydroxyl radical scavengers and antioxidants had no effect. The hemolytic action of cysteine seems to be associated with the stability of the cysteine sulfhydryl group.