SNO-hemoglobin and hypoxic vasodilation

How do red blood cells cause hypoxic vasodilation? The SNO-hemoglobin paradigm.

One of the most intriguing areas of research in erythrocyte physiology is the interaction of hemoglobin with nitric oxide (NO). These two molecules independently fulfill diverse and complex physiological roles, while together they subtly modulate microvascular perfusion in response to second-by-second changes in local metabolic demand, contributing to hypoxic vasodilation. It is through an appr...

Hypoxic Vasodilation by Red Blood Cells

Red blood cells (RBCs) have been ascribed an essential role in matching blood flow to local metabolic demand during hypoxic vasodilation. The vasodilatory function of RBCs evidently relies on the allosteric properties of hemoglobin (Hb), which couple the conformation of Hb to tissue oxygen tension (PO2) and thereby provide a basis for the graded vasodilatory activity that is inversely proportio...

Nitrite Regulates Hypoxic Vasodilation via Myoglobin–Dependent Nitric Oxide Generation Running title: Totzeck et al.; Nitrite Regulates Hypoxic Vasodilation

Adenosine receptor antagonist and augmented vasodilation during hypoxic exercise.

We tested the hypothesis that adenosine contributes to augmented skeletal muscle vasodilation during hypoxic exercise. In separate protocols, subjects performed incremental rhythmic forearm exercise (10% and 20% of maximum) during normoxia and normocapnic hypoxia (80% arterial O2 saturation). In protocol 1 (n = 8), subjects received an intra-arterial administration of saline (control) and amino...

Hydrogen sulfide as an oxygen sensor/transducer in vertebrate hypoxic vasoconstriction and hypoxic vasodilation.

How vertebrate blood vessels sense acute hypoxia and respond either by constricting (hypoxic vasoconstriction) or dilating (hypoxic vasodilation) has not been resolved. In the present study we compared the mechanical and electrical responses of select blood vessels to hypoxia and H2S, measured vascular H2S production, and evaluated the effects of inhibitors of H2S synthesis and addition of the ...