Allen Jason D, Miller Elizabeth M, Schwark Earl, Robbins Jennifer L, Duscha Brian D, Annex Brian H
Department of Medicine, Duke University Medical Center, Wallace Clinic, Center for Living Campus, Durham, NC 27710, USA.
Nitric Oxide. 2009 Jun;20(4):231-7. doi: 10.1016/j.niox.2009.01.002. Epub 2009 Jan 25.
NO is crucial for endothelial function and vascular health. Plasma nitrite (NO(2)(-)) is the main oxidation product of NO and has been shown to reflect changes in eNOS activity. We hypothesized that plasma NO(2)(-) response to physical exercise stress along with physiological endothelial function would be reduced with increasing severity of vascular disease. Subject groups were: (a) risk factors but no vascular disease (RF); (b) Type 2 diabetes with no vascular disease (DM); (c) diagnosed peripheral arterial disease (PAD); and (d) DM+PAD. Venous blood was drawn at rest and 10min following maximal exercise. Plasma samples were analyzed by reductive chemiluminescence. Brachial diameters were imaged prior to, during and following 5min of forearm occlusion (BAFMD). There were no differences in resting plasma NO(2)(-) or BA diameters between groups. The PAD groups had lower age adjusted BAFMD responses (p0.05). Within group analysis revealed an increase in NO(2)(-) in the RF group (+39.3%), no change in the DM (-15.51%), and a decrease in the PAD (-44.20%) and PAD+DM (-39.95%). This was maintained after adjusting for age and VO(2peak) (p0.05). DeltaNO(2)(-) and BAFMD were the strongest independent predictors of VO(2peak) in multivariate linear regression. These findings suggest DeltaNO(2)(-) discriminates severity of cardiovascular disease risk, is related to endothelial function and predicts exercise capacity.
一氧化氮（NO）对于内皮功能和血管健康至关重要。血浆亚硝酸盐（NO₂⁻）是NO的主要氧化产物，已被证明可反映内皮型一氧化氮合酶（eNOS）活性的变化。我们推测，随着血管疾病严重程度的增加，血浆NO₂⁻对体育锻炼应激的反应以及生理内皮功能会降低。受试者分组如下：（a）有风险因素但无血管疾病（RF）；（b）无血管疾病的2型糖尿病（DM）；（c）已诊断的外周动脉疾病（PAD）；（d）DM + PAD。在静息状态和最大运动后10分钟采集静脉血。通过还原化学发光法分析血浆样本。在进行5分钟前臂袖带阻断之前、期间和之后对肱动脉直径进行成像（BAFMD）。各组之间静息血浆NO₂⁻或肱动脉直径无差异。PAD组经年龄调整后的BAFMD反应较低（p<0.05）。组内分析显示，RF组中NO₂⁻增加（+39.3%），DM组无变化（-15.51%），PAD组和PAD + DM组降低（-44.20%和-39.95%）。在调整年龄和最大摄氧量（VO₂peak）后，这种情况依然存在（p<0.05）。在多元线性回归中，ΔNO₂⁻和BAFMD是VO₂peak最强的独立预测因子。这些发现表明，ΔNO₂⁻可区分心血管疾病风险的严重程度，与内皮功能相关，并可预测运动能力。
