Role of retrograde flow in the shear stimulus associated with exercise blood flow.
Role of retrograde flow in the shear stimulus associated with exercise blood flow.
复制标题
逆行流在与运动血流相关的剪切刺激中的作用。
DOI：
10.1111/j.1475-097x.2008.00812.x
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发表时间：
2008
影响因子：
1.8
通讯作者：
Scheuermann,BarryW
中科院分区：
文献类型：
--
作者：
Gonzales,JoaquinU;Thompson,BenjaminC;Thistlethwaite,JohnR;Scheuermann,BarryW
为了检验逆行血流影响运动血流剪切刺激的假设，8名健康男性[25.6 ± 3.1岁（SD）]在两种收缩速度下进行了20分钟的单腿膝关节伸展运动：快（FR，1.5 m s-1）和慢（SR，0.4 m s-1）。 收缩频率（30 cpm）和工作负荷（5 kg）保持恒定，导致两种收缩速度的工作速率均为15·25 W。 采用超声多普勒测量静息和运动时股总动脉内径和血流速度。收缩速度之间的平均血流量没有差异，而在FR收缩期间，顺行（2012·4 ± 379·9 vs 1745·6 ± 601·5 ml min−1;P=0·05）和逆行（121·7 ± 43·0 vs 11·2 ± 6·6 ml min−1;P<0·001）流量分别高于SR收缩。 尽管平均血流反应相似，但FR收缩时的血管阻力低于SR收缩时的血管阻力（0.06 ± 0.01 vs 0.08 ± 0.03单位;P= 0.03），且与剪切率密切相关（汇总数据：r=-0.77，P<0.01）。 逆行血流与运动时较低的血管阻力相关（汇总数据：r=-0.48，P≤ 0.05）。 此外，计算的振荡流指数在FR比SR收缩期间更高，并与逆行流、剪切率和血管阻力显著相关。这些结果表明，逆行血流通过增强血流的振荡行为来影响运动血流的剪切刺激。
To test the hypothesis that retrograde flow influences the shear stimulus of exercise blood flow, eight healthy men [25·6 ± 3·1 years (SD)] performed 20 min of single‐leg knee‐extension exercise at two contraction velocities: fast (FR, 1·5 m s−1) and slow (SR, 0·4 m s−1). Contraction frequency (30 cpm) and workload (5 kg) were kept constant resulting in a work rate of 15·25 W for both contraction velocities. Common femoral artery diameter and blood velocity were measured at rest and during exercise using ultrasound Doppler. Mean blood flow was not different between contraction velocities while antegrade (2012·4 ± 379·9 versus 1745·6 ± 601·5 ml min−1;P=0·05) and retrograde (121·7 ± 43·0 versus 11·2 ± 6·6 ml min−1;P<0·001) flows were higher during FR than SR contractions, respectively. Despite the similar mean blood flow response, vascular resistance was lower during FR than SR contractions (0·06 ± 0·01 versus 0·08 ± 0·03 units;P=0·03) and was closely related to shear rate (pooled data:r= −0·77,P<0·01). Retrograde flow was associated with a lower vascular resistance during exercise (pooled data:r= −0·48,P≤0·05). In addition, calculated oscillatory flow indices were higher during FR than SR contractions and were significantly correlated to retrograde flow, shear rate and vascular resistance. These results indicate that retrograde blood flow influences the shear stimulus of exercise blood flow by enhancing the oscillatory behaviour of flow.