Hemoglobin, nitric oxide and molecular mechanisms of hypoxic vasodilation.
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ABSTRACT:
SUBMITTER: Allen BW
PROVIDER: S-EPMC2785508 | biostudies-other | 2009 Oct
REPOSITORIES: biostudies-other
Publications
Hemoglobin, nitric oxide and molecular mechanisms of hypoxic vasodilation.
Allen Barry W BW Stamler Jonathan S JS Piantadosi Claude A CA
Trends in molecular medicine 20090924 10
The protected transport of nitric oxide (NO) by hemoglobin (Hb) links the metabolic activity of working tissue to the regulation of its local blood supply through hypoxic vasodilation. This physiologic mechanism is allosterically coupled to the O(2) saturation of Hb and involves the covalent binding of NO to a cysteine residue in the beta-chain of Hb (Cys beta93) to form S-nitrosohemoglobin (SNO-Hb). Subsequent S-transnitrosation, the transfer of NO groups to thiols on the RBC membrane and then ...[more]
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