PATHOBIOLOGICAL DETERMINANTS OF ATHEROSCLEROSIS IN YOUTH

此申请是作为美国的参与单位提交的 病理生物学的多中心研究 青年人动脉粥样硬化的决定因素。 的概念基础 应用取决于若干考虑和观察。 其中最主要 这些是：1）主要血管壁的功能完整性， 在大多数情况下，通过胶原纤维的存在来维持;以及 2)胶原蛋白的量以及各种胶原蛋白的相对比例 胶原类型通常在导致 人类出现动脉粥样硬化病变。 此外还 认为导致动脉粥样硬化形成的过程 损伤在长时间间隔内是可操作的。 在这方面，委员会注意到， 参与拟议的联合体安排提供了一个独特的 有机会评价血管胶原状态的潜在改变 在确定的临床前人群中，并将发现与年龄相关联， 总体研究中纳入的受试者的性别、种族和栖息地。 因此，可以预期的是， 这项研究每年将提供大约50个血管组织样本。 样本将来自25名受试者，涉及一个解剖学定义的 胸主动脉节段（20 mm）以及一个解剖学定义的 每例受试者的左回旋支冠状动脉节段（40 mm）。 的 考虑到分析的复杂性， 每年都有样品。 在分析中，每个 将样品去除外膜，通过物理方法细分， 进行氨基酸分析的小等份试样，以评估总 胶原蛋白含量 由于之前的调查显示， 胃蛋白酶的蛋白水解在定量上仅是勉强有效的， 溶解血管组织中的胶原，胶原将被 利用特异性化学切割溶解为肽片段， 氯化萘 然后将所得肽片段在 CM-纤维素和已知含有标记物的色谱柱流出液部分 衍生自I、III、IV和V型胶原蛋白链的肽将被 选择用于通过凝胶渗透HPLC进一步分析，以实现 分离和定量来自不同链的肽。 由于I型、III型、IV型和V型胶原蛋白构成主要胶原蛋白， 存在于血管组织中，这些分析将提供基本数据 任何潜在的数量和/或质量变化， 血管胶原状态作为上述参数的函数。

This application is submitted as a participating unit in the USA investigator-initiated multicenter study of the pathobiological determinants of atherosclerosis in youth. The conceptual basis for the application rests on several considerations and observations. Chief among these are: 1) the functional integrity of the walls of major vessels is, for the most part, maintained through the presence of collagen fibers; and 2) the quantity of collagen as well as the relative proportions of various collagen types is generally altered during the processes leading to the appearance of atherosclerotic lesions in humans. In addition, it is believed that the processes leading to the formation of atherosclerotic lesions are operative over lengthy intervals. In this regard, participation in the contemplated consortium arrangement provides a unique opportunity to evaluate potential modifications of vascular collagen status in a defined preclinical population and correlate the findings with age, sex, race and habitat of the subjects included in the overall study. Accordingly, it is anticipated that the collecting centers involved in the study will provide approximately 50 samples of vascular tissue per year. The samples will be from 25 subjects and involve one anatomically-defined segment (20 mm) of thoracic aorta as well as one anatomically defined segment (40 mm) of the left circumflex coronary artery per subject. The complexity of the contemplated analyses precludes analyses of more than the indicated samples on a yearly basis. With respect to the analyses, each sample will be freed of adventitia, finely divided by physical means, and a small aliquot subjected to amino acid analysis in order to evaluate total collagen content. Since previous investigations have shown that limited proteolysis with pepsin is only marginally effective in quantitatively solubilizing collagens in vascular tissue, the collagens will be solubilized as peptide fragments utilizing specific chemical cleavage with CNBr. The resulting peptide fragments will then be chromatographed on CM-cellulose and portions of the column effluent known to contain marker peptides derived from the chains of type I, III, IV and V collagens will be chosen for further analyses by gel permeation HPLC in order to achieve resolution and quantitation of the peptides derived from various chains. Since type I, III, IV and V collagens constitute the major collagens present in vascular tissues, these analyses will provide basic data concerning any potential quantitative and/or qualitative alterations in vascular collagen status as a function of the parameters noted above.