The last proposed system of RBC vasodilation while in the existence of nitrite is definitely the reduction of nitrite to NO by Hb. Brooks initially examined the nitrite Hb interaction in 1937 which operate was afterwards extended by Doyle in 1981 (Brooks, 1937; Doyle et al., 1981). Nitrite reacts with deoxygenated Hb to type metHb and NO (Brooks, 1