ULTRASOUND EVAL OF FLOW RELATED ARTERIAL DILATION IN HIV INFECTED CHILDREN

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。肱动脉血流介导扩张的超声研究正在成为一种常用的内皮功能研究方法，特别是冠状动脉疾病的风险。在儿童中，股动脉血流介导的扩张已被用于识别家族性血脂异常儿童和川崎综合征儿童的臂动脉血流异常。我们假设股动脉和/或肱动脉血流介导的扩张可能有助于识别HIV感染儿童血流介导的扩张异常，并且可能与目前在接受蛋白酶抑制剂治疗的HIV感染儿童中普遍观察到的胆固醇和甘油三酯异常相关。血管内皮通过释放影响血管张力、血液流动性和炎症的旁分泌因子，在调节血管稳态中起核心作用。一种典型的内皮产物是一氧化氮（NO），它是一种血管扩张剂，是血小板活性、白细胞粘附和平滑肌细胞增殖的抑制剂。一氧化氮合酶（eNOS）由氨基酸l -精氨酸合成一氧化氮，这证实了内皮依赖性血流介导的扩张（FMD）依赖于一氧化氮的产生，这种反应可以在肱动脉或股动脉中检测到，使用本研究提出的非侵入性方法。内皮源性NO生物活性的丧失在动脉粥样硬化的早期和晚期都是重要的。内皮功能障碍的临床相关性已经在成人中建立，证明了内皮功能障碍和心脏事件之间的联系。在儿童中，高分辨率的股动脉或肱动脉超声被用于测量反应性充血和甘油三硝酸盐引起的动脉直径变化。血流增加是由放置在股动脉远端大腿周围的血压袖带或放置在上臂周围的血压袖带的通货紧缩引起的。3-5分钟后松开袖带，并从紧缩前30秒到紧缩后90秒连续扫描动脉。10分钟后，第二次静息扫描被记录下来。可以准确检测0.1-0.2 mm的直径变化（Sorensen KE, et al.）。即使在家族性高胆固醇血症的儿童中，内皮依赖性扩张的损害也是早期的，并且与脂蛋白9a有关。j .中国。投资。1994;93:50-55)。

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. Ultrasound study of brachial artery flow-mediated dilation is emerging as a commonly used test for investigation of endothelial function, specifically risk for coronary artery disease. In children, femoral artery flow mediated dilation has been used to identify abnormalities in children with familial dyslipidemia and brachial artery flow in children with Kawasaki Syndrome. We hypothesize femoral and/or brachial artery flow mediated dilation may be useful in identifying abnormalities in flow mediated dilation in HIV infected children and may correlate with the observed abnormalities in cholesterol and triglycerides now commonly observed in HIV infected children treated with protease inhibitors. The vascular endothelium plays a central role in the regulation of vascular homeostasis by releasing paracrine factors that influence vascular tone, blood fluidity, and inflammation. A prototypical and relevant endothelial product is nitric oxide (NO), which is a vasodilator and an inhibitor of platelet activity, leukocyte adhesion, and smooth muscle cell proliferation. NO is synthesized from the amino acid L-arginine by the enzyme nitric oxide synthase (eNOS), which established that endothelium-dependent flow-mediated dilation (FMD) is dependent on nitric oxide production and that this response can be detected in the brachial or femoral artery using the non-invasive methodology proposed for the present study. Loss of the biologic activity of endothelium-derived NO is important in both the early and later stages of atherosclerosis. The clinical relevance of endothelial dysfunction has been established in adults by demonstrating a link between endothelial dysfunction and cardiac events. In children, high resolution ultrasound of the femoral or brachial artery has been used to measure changes in arterial diameter in response to reactive hyperemia and to glycertrinitrite. Flow increase is induced by deflation of a blood pressure cuff placed around the thigh distal to the femoral artery or deflation of a blood pressure cuff placed around the upper arm. The cuff is released after 3-5 minutes and the artery scanned continuously from 30 seconds before to 90 seconds after deflations. Ten minutes later, a second resting scan is recorded. Changes in diameter of 0.1-0.2 mm can be detected accurately (Sorensen KE, et al. Impairment of endothelial-dependent dilatation is an early even in children with Familial Hypercholesterolemia and is related to the lipoprotein 9a) (Level. J. Clin. Invest. 1994;93:50-55).