Additional Names: Hemiglobin; ferrihemoglobin; met Hb
Literature References: Oxidation product of the normal blood pigment, hemoglobin, in which the iron is present in the ferric state. Methemoglobin may be formed through the direct action of oxidants, through the coaction of hydrogen donors and atmospheric oxygen, or through the autoxidation of hemoglobin which occurs to a small extent in normal blood. Methemoglobin does not have the capacity to combine with molecular oxygen. Reviews: Bodansky, Pharmacol. Rev. 3, 144 (1951); Jaffé in The Red Blood Cell, Bishop, Surgenor, Eds. (Academic Press, 1964) pp 397-422.
Properties: Cleaved by acids and bases to yield globin and ferriprotoporphyrin.