Research Institute for Sport and Exercise Sciences, Tom Reilly Building, Liverpool John Moores University, Byrom St., Liverpool, L3 3AF, UK.
Eur J Appl Physiol. 2012 Feb;112(2):421-7. doi: 10.1007/s00421-011-1993-1. Epub 2011 May 15.
Flow mediated dilation (FMD) is a surrogate marker of arterial function which can be improved by exercise training. To date, no study has assessed the magnitude of FMD changes in response to exercise training between groups of mono- (MZ) and di-zygotic (DZ) twins. The purpose of this study was therefore to compare FMD in MZ- and DZ twins before and after identical exercise training interventions. At baseline, FMD was assessed using high resolution Duplex ultrasound in 12 twin pairs (6 MZ pairs 13.5 ± 0.8 years, 6 DZ pairs 13.4 ± 0.8 years). Twins completed 8 weeks of exercise training (65-85% HR(max)), consisting of three 45-min sessions per week. Change (Δ) scores were entered into twin versus twin intraclass correlation analyses by group. Change in %body fat (r = 0.63, P = 0.05) was significantly correlated in the MZ, but not the DZ group (r = 0.31, P = 0.23). Change in FMD was also highly correlated in MZ (r = 0.74, P = 0.02) but not in the DZ group (r = 0.37, P = 0.18). Heritability of ΔFMD was estimated at 0.74. Exercise induced changes in FMD were similar within sets of monozygotic twins but not dizygotic twins. These data suggest that a significant portion of the arterial function response to exercise training may be genetically determined.
血流介导的扩张（FMD）是一种动脉功能的替代标志物，可以通过运动训练来改善。迄今为止，尚无研究评估单卵（MZ）和双卵（DZ）双胞胎之间运动训练对 FMD 变化的影响。因此，本研究的目的是比较 MZ 和 DZ 双胞胎在进行相同的运动训练干预前后的 FMD。在基线时，通过高分辨率双功能超声在 12 对双胞胎（6 对 MZ 双胞胎，年龄 13.5±0.8 岁，6 对 DZ 双胞胎，年龄 13.4±0.8 岁）中评估 FMD。双胞胎完成 8 周的运动训练（65-85%HR(max)），每周进行三次 45 分钟的训练。按组将变化（Δ）评分输入双胞胎与双胞胎的内部类间相关分析中。在 MZ 组中，体重变化（r=0.63，P=0.05）与 FMD 变化呈显著相关，但在 DZ 组中（r=0.31，P=0.23）则没有。在 MZ 组中，FMD 的变化也高度相关（r=0.74，P=0.02），但在 DZ 组中（r=0.37，P=0.18）则没有。ΔFMD 的遗传力估计为 0.74。在 MZ 双胞胎中，运动引起的 FMD 变化在同组内相似，但在 DZ 双胞胎中则不然。这些数据表明，运动训练对动脉功能的反应有相当一部分可能是由遗传决定的。
