Matched increases in cerebral artery shear stress, irrespective of stimulus, induce similar changes in extra-cranial arterial diameter in humans
Matched increases in cerebral artery shear stress, irrespective of stimulus, induce similar changes in extra-cranial arterial diameter in humans
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无论刺激如何，脑动脉剪切应力的相应增加都会引起人类颅外动脉直径的类似变化
DOI：
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发表时间：
2017
影响因子：
6.3
通讯作者：
D. Green
中科院分区：
文献类型：
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作者：
Kurt J. Smith;R. Hoiland;R. Grove;H. Mckirdy;L. Naylor;P. Ainslie;D. Green
动脉切应力在调节脑血管对生理刺激（运动和高碳酸血症）的反应中的机制作用知之甚少。我们假设，如果剪切应力是动脉扩张的关键调节因子，那么由不同的生理刺激引起的剪切力的匹配增加将触发颅外大动脉的类似扩张。受试者（n = 10）参加了3个30分钟的实验干预，每个干预间隔≥48小时：（1）轻度高碳酸血症（FICO 2：≤ 0.045）;（2）次最大循环（EX; 60%HR储备）;或（3）休息（时间匹配对照，CTRL）。在基线、干预期间和干预后评估颈内动脉和椎动脉（伊卡、VA）的血流、直径和剪切率（通过多普勒超声）。高碳酸血症和EX引起通过伊卡和VA的血流和剪切率的相似升高（p < 0.001），均大于CTRL。高碳酸血症（5.3 ± 0.8和4.4 ± 2.0%）和EX（4.7 ± 0.7和4.7 ± 2.2%）引起的伊卡和VA直径的血管舒张相似，且大于CTRL（p < 0.001）。我们的研究结果表明，相匹配的水平的剪切，无论其驱动刺激，诱导类似的颅外动脉扩张。我们首次在人类中证明了内皮细胞在调节脑血管对体内常见生理刺激的反应中的重要机制作用。
The mechanistic role of arterial shear stress in the regulation of cerebrovascular responses to physiological stimuli (exercise and hypercapnia) is poorly understood. We hypothesised that, if shear stress is a key regulator of arterial dilation, then matched increases in shear, induced by distinct physiological stimuli, would trigger similar dilation of the large extra-cranial arteries. Participants (n = 10) participated in three 30-min experimental interventions, each separated by ≥48 h: (1) mild-hypercapnia (FICO2:∼0.045); (2) submaximal cycling (EX; 60%HRreserve); or (3) resting (time-matched control, CTRL). Blood flow, diameter, and shear rate were assessed (via Duplex ultrasound) in the internal carotid and vertebral arteries (ICA, VA) at baseline, during and following the interventions. Hypercapnia and EX produced similar elevations in blood flow and shear rate through the ICA and VA (p < 0.001), which were both greater than CTRL. Vasodilation of ICA and VA diameter in response to hypercapnia (5.3 ± 0.8 and 4.4 ± 2.0%) and EX (4.7 ± 0.7 and 4.7 ± 2.2%) were similar, and greater than CTRL (p < 0.001). Our findings indicate that matched levels of shear, irrespective of their driving stimulus, induce similar extra-cranial artery dilation. We demonstrate, for the first time in humans, an important mechanistic role for the endothelium in regulating cerebrovascular response to common physiological stimuli in vivo.
DOI：
10.3233/jad-122011
发表时间：
2013
期刊：
Journal of Alzheimer's disease : JAD
影响因子：
--
作者：
Glodzik L;Randall C;Rusinek H;de Leon MJ
通讯作者：
de Leon MJ