Winer N, Sowers J R, Weber M A
Department of Medicine, Division of Endocrinology, Diabetes, and Hypertension, SUNY Health Science Center at Brooklyn, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
J Clin Hypertens (Greenwich). 2001 May-Jun;3(3):145-52. doi: 10.1111/j.1524-6175.2001.00704.x.
Sex hormones exert important effects on the vasculature. Female sex hormones have been reported to enhance endothelial function, reduce oxidative stress, and protect against atherosclerosis. However, the effects of estrogen on vascular compliance have not been studied. Recently, noninvasive instrumentation that estimates vascular compliance by recording the radial artery pulse contour has been introduced. Reductions in the oscillatory or reflected component of the diastolic waveform have been observed in various clinical conditions, including hypertension, diabetes mellitus, and congestive heart failure, and may reflect endothelial dysfunction at the site of resistance vessels. In this study the authors examined gender-related vascular compliance in a cohort of young, healthy, predominantly nonsmoking, medication-free men and women to determine the influence of cardiovascular risk factors, including family and social history, serum lipids, plasma homocysteine, and insulin levels on vascular compliance.
The volunteers, consisting of 151 healthy men and women (mean age 24A+/-4 years) completed a questionnaire detailing family and social history, medication use, and exercise habits. Large (C1) and small (C2) vessel compliance and various cardiovascular parameters were derived from arterial pulse wave contour analysis. Systolic, diastolic, and mean arterial blood pressure, pulse pressure, and pulse rate were determined simultaneously by oscillometry. Blood for fasting serum lipids, plasma homocysteine, and serum insulin were obtained in a subset of 135 subjects.
The questionnaire revealed that 38% of parents had a history of hypertension, 31% had dyslipidemia, and 15% had coronary heart disease. C2 was lower in subjects with parental dyslipidemia. Compared to men, women had lower C2; lower systolic blood pressure, mean arterial pressure, and pulse pressure; higher serum high-density lipoprotein cholesterol; lower serum triglycerides; and lower plasma homocysteine, but similar serum insulin levels. C1 correlated with height and pulse pressure, whereas C2 was proportional to height and weight and inversely related to systemic vascular resistance. Multivariate regression analysis showed that stroke volume, total vascular impedance, cardiac output, female gender, and systemic vascular resistance independently predicted changes in C2, but that height was not a significant factor.
Women have reduced C2 despite lower systolic blood pressure and pulse pressure and more favorable lipid and homocysteine levels. C2 is independent of height and is lower in subjects with parental dyslipidemia. These data indicate that female sex hormones have unexpected negative effects on small vessel compliance. They may help to explain why premenopausal women hospitalized for myocardial infarction have higher mortality rates than men of the same age.
性激素对血管系统有重要影响。据报道，女性性激素可增强内皮功能、降低氧化应激并预防动脉粥样硬化。然而，雌激素对血管顺应性的影响尚未得到研究。最近，已引入通过记录桡动脉脉搏轮廓来估计血管顺应性的非侵入性仪器。在包括高血压、糖尿病和充血性心力衰竭在内的各种临床情况下，已观察到舒张期波形的振荡或反射成分减少，这可能反映了阻力血管部位的内皮功能障碍。在本研究中，作者检查了一组年轻、健康、主要不吸烟且未服用药物的男性和女性的性别相关血管顺应性，以确定包括家族和社会病史、血脂、血浆同型半胱氨酸和胰岛素水平在内的心血管危险因素对血管顺应性的影响。
151名健康男性和女性志愿者（平均年龄24±4岁）完成了一份详细的问卷，内容包括家族和社会病史、用药情况和运动习惯。通过动脉脉搏波轮廓分析得出大血管（C1）和小血管（C2）的顺应性以及各种心血管参数。通过示波法同时测定收缩压、舒张压和平均动脉压、脉压和脉搏率。在135名受试者的子集中采集空腹血脂、血浆同型半胱氨酸和血清胰岛素的血液样本。
问卷显示，38%的父母有高血压病史，31%有血脂异常，15%有冠心病。父母患有血脂异常的受试者C2较低。与男性相比，女性的C2较低；收缩压、平均动脉压和脉压较低；血清高密度脂蛋白胆固醇较高；血清甘油三酯较低；血浆同型半胱氨酸较低，但血清胰岛素水平相似。C1与身高和脉压相关，而C2与身高和体重成正比，与全身血管阻力成反比。多变量回归分析表明，每搏输出量、总血管阻抗、心输出量、女性性别和全身血管阻力独立预测C2的变化，但身高不是一个显著因素。
尽管女性收缩压和脉压较低，血脂和同型半胱氨酸水平更有利，但C2仍降低。C2与身高无关，父母患有血脂异常的受试者C2较低。这些数据表明，女性性激素对小血管顺应性有意外的负面影响。它们可能有助于解释为什么因心肌梗死住院的绝经前女性死亡率高于同龄男性。
