Methemoglobin formation and reduction in relation to hemoglobin oxygen affinity.

It is suggested that although the high oxygen affinity hemoglobins (Hb LR) (beta 143(H21)His leads to Gln) with stabilization of R quaternary conformation is not more susceptible to the oxidizing effect of nitrites in vitro, in an in vivo situation where hemoglobin is partly deoxygenated, it might be more susceptible to methemoglobin formation due to higher oxidation and lower reduction rate.