Ascorbic acid does not affect large elastic artery compliance or central blood pressure in young and older men
Ascorbic acid does not affect large elastic artery compliance or central blood pressure in young and older men
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DOI：
10.1152/ajpheart.00879.2003
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发表时间：
2004-04-01
影响因子：
4.8
通讯作者：
Seals, DR
中科院分区：
文献类型：
--
作者：
Eskurza, I;Monahan, KD;Seals, DR
随着年龄的增长，中央（心胸）循环中的大弹性动脉顺应性降低，动脉血压（BP）升高。活性氧可以调节中枢动脉顺应性和血压在人类，氧化应激可能会导致不利的变化与老化。如果是这样的话，抗氧化剂的管理可能有有益的影响。Young（Y;对26 +/- 1岁，平均+/- SE）和老年（O; 63 +/- 2岁，平均+/- SE）健康男性在基线和急性（静脉输注; Y：n = 13，O：n = 12）和慢性（500 mg/天，持续30天; Y：n = 10，O：n = 10）抗坏血酸（维生素C）给药期间进行了研究。基线时，外周（肱动脉）血压在两组中没有差异，但颈动脉顺应性低43（1.2 ± 0.1 vs. 2.1 ± 0.1 mm（2）/mmHg x 10（-1），P < 0.01）和中央（颈动脉）血压（收缩压：116 +/- 5 vs. 101 +/- 3 mmHg，P < 0.05，脉压：43 =/- 4 vs. 36 +/- 3 mmHg，P = 0.16），颈动脉增强指数（AIx; 27.8 +/- 7.8 vs. - 20.0 +/-6.6%，P < 0.001）和主动脉脉搏波速度（PWV; 950 +/- 88 vs. 640 +/- 38 cm/s，P < 0.01）在老年男性中更高。血浆抗坏血酸浓度在基线时没有差异（Y：71 +/- 5 vs. O：61 +/- 7 mumol/l，P = 0.23），升高（P < 0.001）至输注期间超生理水平（Y：1，240 +/- 57和O：1，056 +/- 83 μ mol/l），补充后略有升高（P < 0.001 vs.基线）（Y：96 +/- 5 μ mol/l vs. O：85 +/- 6）。抗坏血酸输注和补充均不影响外周血压、心率、颈动脉顺应性、中心血压、颈动脉AIx和主动脉PWV（均P > 0.26）。这些结果表明，健康男性大弹性动脉顺应性和中心血压随年龄增长的不利变化不是1）由抗坏血酸敏感的氧化应激（输注实验）介导的，也不是2）受短期、每日适量补充抗坏血酸（维生素C）的影响。
Large elastic artery compliance is reduced and arterial blood pressure ( BP) is increased in the central (cardiothoracic) circulation with aging. Reactive oxygen species may tonically modulate central arterial compliance and BP in humans, and oxidative stress may contribute to adverse changes with aging. If so, antioxidant administration may have beneficial effects. Young (Y; 26 +/- 1 yr, mean +/- SE) and older (O; 63 +/- 2 yr, mean +/- SE) healthy men were studied at baseline and during acute ( intravenous infusion; Y: n = 13, O: n = 12) and chronic ( 500 mg/day for 30 days; Y: n = 10, O: n = 10) administration of ascorbic acid ( vitamin C). At baseline, peripheral ( brachial artery) BP did not differ in the two groups, but carotid artery compliance was 43% lower (1.2 +/- 0.1 vs. 2.1 +/- 0.1 mm(2)/mmHg x 10(-1), P < 0.01) and central ( carotid) BP (systolic: 116 +/- 5 vs. 101 +/- 3 mmHg, P < 0.05, and pulse pressure: 43 =/- 4 vs. 36 +/- 3 mmHg, P = 0.16), carotid augmentation index (AIx; 27.8 +/- 7.8 vs. - 20.0 +/- 6.6%, P < 0.001), and aortic pulse wave velocity (PWV; 950 +/- 88 vs. 640 +/- 38 cm/s, P < 0.01) were higher in the older men. Plasma ascorbic acid concentrations did not differ at baseline (Y: 71 +/- 5 vs. O: 61 +/- 7 mumol/l, P = 0.23), increased (P < 0.001) to supraphysiological levels during infusion ( Y: 1,240 +/- 57 and O: 1,056 +/- 83 mu mol/l), and were slightly elevated ( P < 0.001 vs. baseline) with supplementation ( Y: 96 +/- 5 mumol/l vs. O: 85 +/- 6). Neither ascorbic acid infusion nor supplementation affected peripheral BP, heart rate, carotid artery compliance, central BP, carotid AIx, or aortic PWV ( all P > 0.26). These results indicate that the adverse changes in large elastic artery compliance and central BP with aging in healthy men are not 1) mediated by ascorbic acid-sensitive oxidative stress ( infusion experiments) and 2) affected by short-term, moderate daily ascorbic acid ( vitamin C) supplementation.