Reduced arterial vasodilatation in response to hypoxia impairs cerebral and peripheral oxygen delivery in hypertensive men

摘要

Key points class="unordered" style="list-style-type:disc" id="tjp12832-list-0001">Hypoxaemia evokes a repertoire of homeostatic adjustments that maintain oxygen supply to organs and tissues including the brain and skeletal muscles.Because hypertensive patients have impaired endothelial‐dependent vasodilatation and an increased sympathetic response to arterial oxygen desaturation, we investigated whether hypertension impairs isocapnic hypoxia‐induced cerebral and skeletal muscle hyperaemia to an extent that limits oxygen supply.In middle‐aged hypertensive men, vertebral and femoral artery blood flow do not increase in response to isocapnic hypoxia, limiting brain and peripheral hyperaemia and oxygen supply.Increased chemoreflex‐induced sympathetic activation impairs skeletal muscle perfusion and oxygen supply, whereas an attenuation of local vasodilatory signalling in the posterior cerebrovasculature reduced brain hyperperfusion of hypertensive middle‐aged men in response to isocapnic hypoxia.