Nitrite has long been known to be vasoactive when present at large concentrations but it
was thought to be inactive under physiological conditions. Surprisingly, we have recently
shown that supraphysiological and near physiological concentrations of nitrite cause
vasodilation in the human circulation. These effects appeared to result from reduction of
nitrite by deoxygenated hemoglobin. Thus, nitrite was proposed to play a role in hypoxic
vasodilation. We now discuss these results in the context of nitrite reacting with hemoglobin …