Nitric oxide plays an important role in maintaining endothelial function, while increased oxidative stress may lead to nitric oxide inactivation and cardiovascular disease. If nitric oxide biosynthesis/bioavailability is already suppressed early in life, it may potentially predispose an individual to the early development of cardiovascular disease. We therefore aimed to identify differences in nitric oxide-related markers (urinary nitrate, nitrite and the nitrate-to-nitrite ratio (U_NOxR)) between young black and white individuals, and whether these markers are associated with blood pressure and carotid intima media thickness. We included black and white healthy boys (n = 80; aged 6–8 years) and men (n = 510; 20–30 years) and measured blood pressure and carotid intima media thickness, along with urinary biochemical markers including nitrate and nitrite. The black boys and men had lower nitrate and U_NOxR (all p ≤ 0.003) than their white counterparts. In single and multiple regression analyses, we found an inverse association of diastolic blood pressure in the black boys (adj. R² = 0.27; β = –0.32; p = 0.030), and systolic blood pressure in black men (adj. R² = 0.07; β = –0.13; p = 0.036) with nitrate. Carotid intima media thickness associated inversely with U_NOxR in the black men (adj. R² = 0.02; β = –0.14; p = 0.023), but not in the boys. Lower urinary nitrate in black boys and young men was associated negatively with blood pressure, suggesting that potentially lower nitric oxide bioavailability in young black individuals may contribute to hypertension development in later life.

中文翻译：

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一氧化氮相关的标志物与黑人男孩的血压成反比：ASOS和African-PREDICT研究。

一氧化氮在维持内皮功能中起着重要作用，而增加的氧化应激可能导致一氧化氮失活和心血管疾病。如果一氧化氮的生物合成/生物利用度在生命的早期就已被抑制，则可能使个体更易患心血管疾病。因此，我们旨在确定年轻黑人和白人之间一氧化氮相关标志物（尿中的硝酸盐，亚硝酸盐和硝酸盐与亚硝酸盐之比（U _NOx R））的差异，以及这些标志物是否与血压和颈动脉内膜有关介质厚度。我们纳入了黑人和白人健康男孩（n  = 80； 6-8岁）和男人（n = 510; 20–30岁），并测量血压和颈动脉内膜中层厚度，以及尿液生化标志物，包括硝酸盐和亚硝酸盐。黑男孩和男人有较低的硝酸盐和U_氮氧化物R（所有p  ≤0.003）高于白人。在单次和多次回归分析中，我们发现黑人男孩的舒张压呈负相关（调节R ²  = 0.27；β  = –0.32；p  = 0.030），而黑人男性的收缩压呈负相关（调节R ²  = 0.07；β  = –0.13；p  = 0.036）和硝酸盐。颈动脉内膜中层厚度与U _NOx成反比黑人男子中的R（调整R ²  = 0.02；β  = –0.14；p  = 0.023），但男孩中没有。黑人男孩和年轻人中较低的尿液硝酸盐含量与血压呈负相关，这表明潜在的黑人年轻人中一氧化氮生物利用度降低可能会导致以后的高血压发展。