Delaney Erin P, Young Colin N, Disabatino Angela, Stillabower Michael E, Farquhar William B
Department of Health, Nutrition and Exercise Sciences, University of Delaware, Newark, DE 19716, USA.
J Appl Physiol (1985). 2008 Sep;105(3):894-901. doi: 10.1152/japplphysiol.90574.2008. Epub 2008 Jul 17.
Hypertensive (HTN) animal models demonstrate lower venous compliance as well as increased venous tone and responsiveness compared with normotensive (NTN) controls. However, the extent to which findings in experimental animals can be extended to humans is unknown. Forearm and calf venous compliance were quantified in 9 NTN (23 +/- 1 yr) and 9 HTN (24 +/- 1 yr) men at baseline, after administration of nitroglycerin (NTG), during a cold pressor test (CP), and post-handgrip exercise ischemia (PEI). Individual pressure-volume relationships from a cuff deflation protocol (1 mmHg/s) were modeled with a quadratic regression. Regression parameters beta(1) and beta(2) were used to calculate compliance. A one-way ANOVA was used to compare the beta parameters and a repeated-measures ANOVA was used to compare volumes across all pressures (between groups at baseline and within groups during perturbations). Limb venous compliance was similar between groups (forearm: NTN beta(1) = 0.11 +/- 0.01 and beta(2) = -0.00097 +/- 0.0001, HTN beta(1) = 0.10 +/- 0.01 and beta(2) = -0.00088 +/- 0.0001; calf: NTN beta(1) = 0.12 +/- 0.01 and beta(2) = -0.00102 +/- 0.0001, HTN beta(1) = 0.11 +/- 0.01 and beta(2) = -0.00090 +/- 0.0001). However, at baseline, volume across all pressures (i.e., capacitance) was lower in the forearm (P < or = 0.01) and tended to be lower in the calf (P = 0.08) in HTN subjects. Venous compliance was not altered by any perturbation in either group. Forearm volume was increased during NTG in HTN subjects only. While venous compliance was similar between NTN and HTN adults, HTN adults have lower forearm venous capacitance (volume) which is increased with NTG. These data suggest that young HTN adults may have augmented venous smooth muscle tone compared with NTN controls.
与正常血压（NTN）对照组相比，高血压（HTN）动物模型表现出较低的静脉顺应性以及增强的静脉张力和反应性。然而，实验动物的研究结果在多大程度上能够推广到人类尚不清楚。对9名NTN组（23±1岁）和9名HTN组（24±1岁）男性在基线、给予硝酸甘油（NTG）后、冷加压试验（CP）期间以及握力运动后缺血（PEI）时的前臂和小腿静脉顺应性进行了量化。通过二次回归对袖带放气方案（1 mmHg/s）的个体压力-容积关系进行建模。回归参数β(1)和β(2)用于计算顺应性。采用单因素方差分析比较β参数，采用重复测量方差分析比较所有压力下的容积（基线时组间以及干预期间组内）。两组之间的肢体静脉顺应性相似（前臂：NTN组β(1)=0.11±0.01，β(2)=-0.00097±0.0001；HTN组β(1)=0.10±0.01，β(2)=-0.00088±0.0001；小腿：NTN组β(1)=0.12±0.01，β(2)=-0.00102±0.0001；HTN组β(1)=0.11±0.01，β(2)=-0.00090±0.0001）。然而，在基线时，HTN受试者前臂所有压力下的容积（即容量）较低（P≤0.01），小腿的容积有降低趋势（P=0.08）。两组中任何干预均未改变静脉顺应性。仅HTN受试者在给予NTG期间前臂容积增加。虽然NTN和HTN成年人的静脉顺应性相似，但HTN成年人的前臂静脉容量（容积）较低，且给予NTG后会增加。这些数据表明，与NTN对照组相比，年轻的HTN成年人可能具有增强的静脉平滑肌张力。
