Scholten Ralph R, Spaanderman Marc E A, Green Daniel J, Hopman Maria T E, Thijssen Dick H J
Department of Physiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; Department of Obstetrics and Gynaecology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands;
Research School GROW, Maastricht University Medical Centre, Maastricht, The Netherlands;
Am J Physiol Heart Circ Physiol. 2014 Aug 1;307(3):H418-25. doi: 10.1152/ajpheart.00128.2014. Epub 2014 Jun 6.
Blood flow patterns in conduit arteries characterized by high levels of retrograde shear stress can be detrimental for vascular health. In this study we examined whether retrograde shear rate and endothelial function are related in healthy and formerly preeclamptic (PE) women and whether this relationship is altered by exercise training. Formerly PE women (32 ± 4 yr, n = 20) and controls (32 ± 4 yr, n = 20), all 6-12 mo postpartum, performed 12-wk aerobic exercise training. We measured brachial artery shear rate (SR) and endothelial function by flow-mediated dilation (FMD, echo-Doppler). We additionally performed power spectral analysis of heart rate variability and calculated low-frequency/high-frequency (LF/HF) ratio. Antegrade SR was not different between groups, while retrograde SR was significantly higher and FMD% lower in PE women compared with controls (both P < 0.05). Retrograde shear correlated strongly with FMD% in PE women and controls (P < 0.05). LF/HF ratio inversely correlated with brachial artery retrograde SR and FMD% (both P < 0.05) in PE women and controls. Exercise training reduced retrograde shear, improved FMD%, and reduced LF/HF ratios similarly in both groups (all P < 0.05). Training-induced changes in retrograde SR correlated with changes in FMD% and LF/HF ratio. A higher brachial artery retrograde SR relates to lower brachial artery endothelial function, in both controls and formerly PE women. Exercise training improves retrograde SR, while the magnitude of this change correlated strongly with improvements in FMD and reductions in LF/HF ratio. Therefore, the impact of PE and exercise training on endothelial health may, at least partly, be related to retrograde shear rate.
以高水平逆行剪切应力为特征的输送动脉中的血流模式可能对血管健康有害。在本研究中，我们检查了健康和既往患有先兆子痫（PE）的女性中逆行剪切速率与内皮功能是否相关，以及这种关系是否会因运动训练而改变。既往患有PE的女性（32±4岁，n = 20）和对照组（32±4岁，n = 20），均在产后6 - 12个月，进行了为期12周的有氧运动训练。我们通过血流介导的血管舒张（FMD，超声多普勒）测量肱动脉剪切速率（SR）和内皮功能。我们还进行了心率变异性的功率谱分析，并计算了低频/高频（LF/HF）比值。顺行SR在两组之间没有差异，而与对照组相比，PE女性的逆行SR显著更高且FMD%更低（两者P < 0.05）。在PE女性和对照组中，逆行剪切与FMD%密切相关（P < 0.05）。在PE女性和对照组中，LF/HF比值与肱动脉逆行SR和FMD%呈负相关（两者P < 0.05）。运动训练在两组中同样降低了逆行剪切，改善了FMD%，并降低了LF/HF比值（所有P < 0.05）。训练引起的逆行SR变化与FMD%和LF/HF比值的变化相关。在对照组和既往患有PE的女性中，较高的肱动脉逆行SR与较低的肱动脉内皮功能相关。运动训练改善了逆行SR，而这种变化的幅度与FMD的改善和LF/HF比值的降低密切相关。因此，PE和运动训练对内皮健康的影响可能至少部分与逆行剪切速率有关。
