Miranda K. Traylor, Genevieve B. Batman, Kylie N. Sears, Kyndall V. Ransom, Shane M. Hammer, Joshua L. Keller
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引用次数: 0
Abstract
Objective
We examined sex-specific microvascular reactivity and hemodynamic responses under conditions of augmented resting blood flow induced by passive heating compared to normal blood flow.
Methods
Thirty-eight adults (19 females) completed a vascular occlusion test (VOT) on two occasions preceded by rest with or without passive heating in a randomized, counterbalanced order. Skeletal muscle tissue oxygenation (StO2, %) was assessed with near-infrared spectroscopy (NIRS), and the rate of desaturation and resaturation as well as maximal StO2 (StO2max) and prolonged hypersaturation (area under the curve, StO2AUC) were quantified. Before the VOT, brachial artery blood flow (BABF), vascular conductance, and relative BABF (BABF normalized to forearm lean mass) were determined. Sex × condition ANOVAs were used. A p-value ≤.05 was considered statistically significant.
Results
Twenty minutes of heating increased BABF compared to the control (102.9 ± 28.3 vs. 36.0 ± 20.9 mL min−1; p < .01). Males demonstrated greater BABF than females (91.9 ± 34.0 vs. 47.0 ± 19.1 mL min−1; p < .01). There was no sex difference in normalized BABF. There were no significant interactions for NIRS-VOT outcomes, but heat did increase the rate of desaturation (−0.140 ± 0.02 vs. −0.119 ± 0.03% s−1; p < .01), whereas regardless of condition, males exhibited greater rates of resaturation and StO2max than females.
Conclusions
These results suggest that blood flow is not the primary factor causing sex differences in NIRS-VOT outcomes.
目的我们研究了与正常血流相比,在被动加热引起静息血流增加的条件下,不同性别的微血管反应性和血流动力学反应:38名成年人(19名女性)完成了两次血管闭塞测试(VOT),测试前以随机、平衡的顺序进行了休息,同时进行或不进行被动加热。用近红外光谱(NIRS)评估骨骼肌组织氧饱和度(StO2,%),并对去饱和度和再饱和度以及最大 StO2(StO2max)和长时间高饱和度(曲线下面积,StO2AUC)进行量化。在 VOT 之前,测定了肱动脉血流(BABF)、血管传导和相对 BABF(BABF 与前臂瘦体重的归一化)。采用性别×条件方差分析。P值≤.05为具有统计学意义:结果:与对照组相比,加热 20 分钟可增加 BABF(102.9 ± 28.3 vs. 36.0 ± 20.9 mL min-1 ; p -1 ; p -1 ; p 2max than females):这些结果表明,血流量并不是造成 NIRS-VOT 结果性别差异的主要因素。
期刊介绍:
The journal features original contributions that are the result of investigations contributing significant new information relating to the vascular and lymphatic microcirculation addressed at the intact animal, organ, cellular, or molecular level. Papers describe applications of the methods of physiology, biophysics, bioengineering, genetics, cell biology, biochemistry, and molecular biology to problems in microcirculation.
Microcirculation also publishes state-of-the-art reviews that address frontier areas or new advances in technology in the fields of microcirculatory disease and function. Specific areas of interest include: Angiogenesis, growth and remodeling; Transport and exchange of gasses and solutes; Rheology and biorheology; Endothelial cell biology and metabolism; Interactions between endothelium, smooth muscle, parenchymal cells, leukocytes and platelets; Regulation of vasomotor tone; and Microvascular structures, imaging and morphometry. Papers also describe innovations in experimental techniques and instrumentation for studying all aspects of microcirculatory structure and function.