Blood flow regulation by S-nitrosohemoglobin in the physiological oxygen gradient
Blood flow regulation by S-nitrosohemoglobin in the physiological oxygen gradient
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DOI：
10.1126/science.276.5321.2034
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发表时间：
1997-06-27
期刊：
影响因子：
56.9
通讯作者：
Piantadosi, CA
中科院分区：
文献类型：
--
作者：
Stamler, JS;Jia, L;Piantadosi, CA
氧与血红蛋白中的血红素铁结合，促进一氧化氮(NO)与半胱氨酸β93的结合，形成S亚硝基血红蛋白。脱氧伴随着S-亚硝基血红蛋白[从R(加氧)到T(脱氧)结构]的变构转变，释放NO基团，S-亚硝基血红蛋白收缩R结构中的血管并减少脑灌注量，松弛血管以改善T结构中的血流。因此，通过感知组织中的生理氧气梯度，血红蛋白利用半胱氨酸β93 SNO位置的构象相关变化，使局部血流与氧气需求保持一致。
The binding of oxygen to heme irons in hemoglobin promotes the binding of nitric oxide (NO) to cysteine beta 93, forming S-nitrosohemoglobin. Deoxygenation is accompanied by an allosteric transition in S-nitrosohemoglobin [from the R (oxygenated) to the T (deoxygenated) structure] that releases the NO group, S-nitrosohemoglobin contracts blood vessels and decreases cerebral perfusion in the R structure and relaxes vessels to improve blood flow in the T structure. By thus sensing the physiological oxygen gradient in tissues, hemoglobin exploits conformation-associated changes in the position of cysteine beta 93 SNO to bring local blood flow into line with oxygen requirements.