Nitrite Reductase Function of Deoxymyoglobin

• DOI: 10.1161/circresaha.107.152488
• Publication Date: 2007-05-11T01:34:15Z
• Authors: Tienush Rassaf; Ulrich Flögel; Christine Drexhage; Ulrike Hendgen-Cotta; Malte Kelm; Jürgen Schrader
• Keywords: Contractility; Deoxygenated Hemoglobin; Cardiac muscle

Although the primary function of myoglobin (Mb) has been considered to be cellular oxygen storage and supply, recent studies have suggested classify Mb as a multifunctional allosteric enzyme. In heart, acts potent scavenger nitric oxide (NO) contributes attenuation oxidative damage. Here we report that dynamic cycle exists in which decrease tissue tension drives conversion from being an NO normoxia producer hypoxia. The generated by reaction deoxygenated with nitrite is functionally relevant leads downregulation cardiac energy status, was not observed mice lacking Mb. As consequence, myocardial consumption reduced contractility dampened wild-type mice. We propose this pathway represents novel homeostatic mechanism mismatch between supply demand muscle translated into fractional increase exhibiting enhanced reductase activity. Thus, may act sensor through can adjust energetics limited supply.