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原文载于:Hypertension Volume 45, Number 6; June, 2005

年龄增长/绝经期变化引起的胸部大弹性动脉的顺应性降低，在绝经后妇女心血管疾病患病率增加中起重要作用。给绝经前妇女静脉快速灌注生理盐水（作为基础对照），给绝经前妇女(n=10; 23±1; mean±SE)和绝经后雌激素缺乏的健康本地妇女(n=21; 55±1 years)灌注高于生理剂量、具有抗氧化作用的抗坏血酸，同时检测她们颈动脉的顺应性。基础对照组中，绝经后妇女颈动脉顺应性比绝经前妇女低56％(P<0.0001)。注射抗坏血酸可使绝经后妇女颈动脉顺应性增加26％(由原来的1.11±0.07上升到1.38±0.08 mm2/mm Hgx10–1; P<0.001)，但对绝经前妇女没有作用(处理前为2.50±0.25，处理后为 2.43±0.20 mm2/mm Hgx10–1)。
颈动脉直径，血压和心率不受抗坏血酸影响。所有研究对象中，用抗坏血酸处理后动脉顺应性的变化与基础腰－臀比例 (r=0.56; P=0.001)，血浆去甲肾上腺素(r=0.58; P=0.001)以及血浆低密度脂蛋白胆固醇(r=0.54; P=0.001)呈正相关。

结论:这些结果提示，氧化应激可能是引起久坐妇女、绝经后雌激素缺乏妇女大弹性动脉顺应性下降的重要机制。异常的脂肪蓄积，交感神经系统兴奋性增强、和低密度脂蛋白胆固醇含量增加，可能也在绝经后妇女由于氧化应激而引起的动脉顺应性下降中起作用。

Ascorbic Acid Selectively Improves Large Elastic Artery Compliance in Postmenopausal Women

The compliance of large elastic arteries in the cardiothoracic region decreases with advancing age/menopause and plays an important role in the increased prevalence of cardiovascular diseases in postmenopausal women. We determined whether oxidative stress contributes to the reduced large elastic artery compliance of postmenopausal women. Carotid artery compliance was measured during acute intravenous infusions of saline (baseline control) and supra physiological doses of the potent antioxidant ascorbic acid in premenopausal (n=10; 23±1; mean±SE) and estrogen-deficient postmenopausal (n=21; 55±1 years) healthy sedentary women. Carotid artery compliance was 56% lower in postmenopausal compared with premenopausal women during baseline control (P<0.0001). Ascorbic acid infusion increased carotid artery compliance by 26% in postmenopausal women (1.11±0.07 to 1.38±0.08 mm2/mm Hgx10–1; P<0.001) but had no effect in premenopausal women (2.50±0.25 versus 2.43±0.20 mm2/mm Hgx10–1). Carotid artery diameter, blood pressure, and heart rate were unaffected by ascorbic acid. In the pooled population, the change in arterial compliance with ascorbic acid correlated with baseline waist-to-hip ratio (r=0.56; P=0.001), plasma norepinephrine (r=0.58; P=0.001), and LDL cholesterol (r=0.54; P=0.001).These results suggest that oxidative stress may be an important mechanism contributing to the reduced large elastic artery compliance of sedentary, estrogen-deficient postmenopausal women. Increased abdominal fat storage, sympathetic nervous system activity, and LDL cholesterol may be mechanistically involved in oxidative stress–associated suppression of arterial compliance in postmenopausal women.