Abstract 1463 Impaired cerebral blood flow regulation in the absence of Hb ßCys93 in a murine exercise model

Tissue hypoxia is associated with oxygen delivery through the regulation of microvascular blood flow, a process known as blood flow autoregulation. Recently, it has been recognized that hemoglobin (Hb) plays a dual role, functioning not only as an oxygen transporter but also as a regulator of microvascular blood flow through the allosterically coupled release of vasodilatory S-nitrosothiol (SNO) in response to hypoxia. In vivo studies with β-globin Cys93Ala (βCys93Ala) mutant mice, which lack S-nitrosohemoglobin (SNO-Hb), exhibit significant impairments in microvascular blood flow and tissue oxygenation, mirroring microcirculatory dysfunction observed in various clinical conditions.