EVALUATE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS AND SYMPATHETIC NERVOUS SYSTEM

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。某些心理因素，包括抑郁，是糖尿病和心血管疾病发展的危险因素，但其机制尚不清楚。这些心理因素引起的神经内分泌变化，特别是下丘脑-垂体-肾上腺（HPA）轴和交感神经系统（SNS）的激活，可能提供一个统一的解释。在基于人群的大型流行病学研究中，评估HPA轴活性作为糖尿病和心血管疾病危险因素的一个限制是缺乏可靠、简便的测量方法来评估其功能。金标准是24小时尿液收集游离皮质醇，在大规模研究中执行起来很麻烦，而且容易发生变化。我们假设唾液皮质醇和肾上腺体积与HPA轴活性密切相关（通过24小时尿液游离皮质醇测量），因此代表了在大规模队列和流行病学研究中评估HPA轴活性的可行方法。本研究的目的是：1)招募50名年龄在18至45岁的非裔美国女性参加一项夜间GCRC研究；2)获得心理特征、人体测量和生化参数的测量；3)进行统计分析，确定24小时尿游离皮质醇与总唾液皮质醇、上午8点、晚上11点唾液皮质醇及肾上腺体积的相关性；(b)胰岛素敏感性和体重指数与24小时尿液游离皮质醇、肾上腺体积和唾液皮质醇的关系；(c) 24小时尿游离皮质醇、肾上腺体积和唾液皮质醇的心理因素。确定可靠、有效的HPA轴活性测量方法，将使它们被纳入心血管疾病和糖尿病的大型前瞻性队列研究，以确定HPA轴过度活跃是否是这两种重要疾病的危险因素，这两种疾病是重大的公共卫生负担。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Certain psychological factors, including depression, are risk factors for the development of diabetes and cardiovascular disease but the mechanism remains unclear. Neuroendocrine changes induced by these psychological factors, specifically activation of the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS), might provide a unifying explanation. One limitation to assessing HPA axis activity in large population-based epidemiological studies as a risk factor for diabetes and cardiovascular disease has been the lack of a reliable, easy measurement to assess its function. The gold standard, a 24-hour urine collection for free cortisol, is cumbersome to perform in large-scale studies and is subject to variability. We hypothesize that salivary cortisol and adrenal volume are tightly correlated with HPA axis activity (as measured by 24-hour urine free cortisol) and therefore represent feasible approaches for assessment of HPA axis activity in large-scale cohort and epidemiological studies. The aims of this study are to 1) enroll 50 African-American women ages 18 to 45 years into an overnight GCRC study; 2) obtain measures of psychological traits, anthropometry, and biochemical parameters; and 3) to conduct statistical analyses to determine the following correlations: (a) 24-hour urine free cortisol with total, 8am, and 11 pm salivary cortisol and with adrenal volume; (b) insulin sensitivity and body-mass index with 24-hour urine free cortisol, adrenal volume, and salivary cortisol; and (c) psychological factors with 24-hour urine free cortisol, adrenal volume, and salivary cortisol. Identifying reliable, efficient measures of HPA axis activity will allow them to be incorporated into large, prospective cohort studies of cardiovascular disease and diabetes to determine if HPA axis hyperactivity is a risk factor for these two important diseases, which are significant public health burdens.