Main Article from Howard Hughes Medical Institute
Blood flow in the microcirculation is regulated by physiological O2 gradients that are coupled to vasodilation and vasoconstriction, but the mechanism underlying this fundamental vascular response (which controls O2 delivery to tissues) has remained a major unanswered question in vascular physiology. The discovery of a previously unknown S-nitrosothiol (SNO) derivative of hemoglobin that has potent vasodilatory activity has changed the picture. Most significantly, the affinity of cysteine β93 for NO is high in the R (or oxy) structure and low in the T (or deoxy) structure. Thus, deoxygenatio...