Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, USA.
Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, USA.
Microvasc Res. 2023 Jul;148:104536. doi: 10.1016/j.mvr.2023.104536. Epub 2023 Apr 5.
Among females in the U.S., Black females suffer the most from cardiovascular disease and stroke. While the reasons for this disparity are multifactorial, vascular dysfunction likely contributes. Chronic whole-body heat therapy (WBHT) improves vascular function, but few studies have examined its acute effect on peripheral or cerebral vascular function, which may help elucidate chronic adaptative mechanisms. Furthermore, no studies have investigated this effect in Black females. We hypothesized that Black females would have lower peripheral and cerebral vascular function relative to White females and that one session of WBHT would mitigate these differences. Eighteen young, healthy Black (n = 9; 21 ± 3 yr; BMI: 24.7 ± 4.5 kg/m) and White (n = 9; 27 ± 3 yr; BMI: 24.8 ± 4.1 kg/m) females underwent one 60 min session of WBHT (49 °C water via a tube-lined suit). Pre- and 45 min post-testing measures included post-occlusive forearm reactive hyperemia (peripheral microvascular function, RH), brachial artery flow-mediated dilation (peripheral macrovascular function, FMD), and cerebrovascular reactivity (CVR) to hypercapnia. Prior to WBHT, there were no differences in RH, FMD, or CVR (p > 0.05 for all). WBHT improved peak RH in both groups (main effect of WBHT: 79.6 ± 20.1 cm/s to 95.9 ± 30.0 cm/s; p = 0.004, g = 0.787) but not Δ blood velocity (p > 0.05 for both groups). WBHT improved FMD in both groups (6.2 ± 3.4 % to 8.8 ± 3.7 %; p = 0.016, g = 0.618) but had no effect on CVR in either group (p = 0.077). These data indicate that one session of WBHT acutely improves peripheral micro- and macrovascular but not cerebral vascular function in Black and White females.
在美国女性中，黑种女性受心血管疾病和中风的影响最大。尽管造成这种差异的原因有很多，但血管功能障碍可能是其中之一。慢性全身热疗（WBHT）可以改善血管功能，但很少有研究探讨其对周围或脑血管功能的急性影响，而这可能有助于阐明慢性适应机制。此外，也没有研究调查这种影响在黑种女性中的作用。我们假设，与白种女性相比，黑种女性的外周和脑血管功能较低，而一次 WBHT 治疗会减轻这些差异。18 名年轻、健康的黑种（n=9；21±3 岁；BMI：24.7±4.5kg/m）和白种（n=9；27±3 岁；BMI：24.8±4.1kg/m）女性接受了一次 60 分钟的 WBHT（通过管衬套装以 49°C 的水）。测试前和 45 分钟后的测量包括缺血后前臂反应性充血（外周微血管功能，RH）、肱动脉血流介导的扩张（外周大血管功能，FMD）以及脑血管对高碳酸血症的反应性（CVR）。在 WBHT 之前，RH、FMD 或 CVR 没有差异（p>0.05）。WBHT 改善了两组的峰值 RH（WBHT 的主要作用：79.6±20.1cm/s 至 95.9±30.0cm/s；p=0.004，g=0.787），但对Δ血流速度没有影响（两组均 p>0.05）。WBHT 改善了两组的 FMD（6.2±3.4%至 8.8±3.7%；p=0.016，g=0.618），但对两组的 CVR 均无影响（p=0.077）。这些数据表明，一次 WBHT 治疗可急性改善黑种和白种女性的外周微血管和大血管功能，但对脑血管功能没有影响。
