Fig. 1.
GSH in the absence of iron accelerated Hb oxidation, but only at very high GSH to Hb ratios. Experiments were performed in the presence of DTPA to ensure that observed effects were iron-independent. The [Hb] was 62 μmol/L in heme, and oxidation was accelerated only when the GSH to heme ratio was ≥2:1; the physiologic ratio is closer to 1:4.