MOLECULAR AND CELLULAR BIOLOGY OF CARDIAC INTERSTITIUM

心脏间质的分子和细胞生物学

• 批准号: 3362243
• 负责人: Allen Mark Samarel
• 金额: $ 12.01万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-01 至 1994-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3362243
• 关键词: cell growth regulation; collagen; endomyocardial fibrosis; fibroblasts; heart cell; heart metabolism; laboratory rat; monoclonal antibody; myogenesis; newborn animals; procollagen; protein biosynthesis; radioimmunoassay; tissue /cell culture; ventricular hypertrophy

A five-year research program is proposed to examine the intracellular mechanisms regulating in vivo collagen metabolism in the normal and hypertrophying rat left ventricular myocardium, as well as in primary cultures of neonatal rat cardiac fibroblasts. The proposed experiments focus upon one particular aspect of collagen metabolism; namely, the intracellular degeneration of newly synthesized procollagens by rat cardiac fibroblasts both in vivo and in cell culture. The intracellular mechanisms regulating this important process are not fully understood, and the potential for pharmacological modulation of the "targeting" of newly synthesized procollagen polypeptides for intracellular destruction would afford another means of reducing collagen accumulation in a variety of cardiovascular diseases associated with interstitial fibrosis. Specific experiments are outlined to estimate in vivo rates of collagen biosynthesis, accumulation, and degradation during normal physiological growth of rat left ventricular myocardium; and during the development of thyroxine-induced LV hypertrophy, and LV hypertrophy following abdominal aortic coarctation. Specific monoclonal antibody probes will also be developed for use in studies of procollagen polypeptide metabolism in cultured neonatal rat cardiac fibroblasts. These sequence- specific monoclonal antibodies (directed against the proaminopeptide domains of rat Type I and Type III procollagen polypeptides) will be used in specific radioimmunoassays for the quantitative analysis of intracellular and secreted procollagens, as well as in the production of immunoadsorbents for the quantitative isolation of newly synthesized and secreted procollagens from cultured cells and media. In addition, primary cultures of neonatal rat cardiac fibroblasts will be characterized with respect to procollagen biosynthesis, secretion, and intracellular degradation during "normal" proliferation in culture, and during a variety of pharmacological interventions known to affect collagen metabolism in the cell culture systems. Finally, the intracellular mechanisms regulating cyclic AMP-dependent "targeting" of newly synthesized procollagens for transport and degradation within fibroblastic lysosomes will be examined. If successful, these studies should provide new and important fundamental information regarding collagen turnover in the cardiac interstitium, as well as provide useful experimental tools for other investigators in this research program interested in cardiac interstitial collagen biochemistry, cellular and molecular biology.

提出了一项为期五年的研究计划，以审查 调节体内胶原代谢的细胞内机制 正常和肥大的大鼠左心室心肌，如 以及在新生大鼠心脏成纤维细胞的原代培养物中。 拟议的实验集中在一个特定的方面， 胶原蛋白代谢;即， 大鼠心脏成纤维细胞新合成的前胶原， 体内和细胞培养中。 细胞内调节机制 这一重要过程尚未完全了解， 用于药理学调节新的“靶向” 用于细胞内破坏的合成前胶原多肽 将提供另一种减少胶原蛋白积聚的方法， 各种心血管疾病与间质性 纤维化 具体的实验概述，以估计在体内 胶原蛋白生物合成、积累和降解速率 在大鼠左心室的正常生理生长过程中 心肌;在甲状腺素诱导的LV发展过程中 肥大和腹主动脉瘤术后LV肥大 缩窄 还将使用特异性单克隆抗体探针。 开发用于前胶原多肽代谢的研究 在培养的新生大鼠心脏成纤维细胞中。 这些序列- 特异性单克隆抗体（针对 大鼠I型和III型前胶原的前氨基肽结构域 多肽）将用于特异性放射免疫测定， 细胞内和分泌的前胶原的定量分析， 以及用于制备免疫吸附剂， 定量分离新合成和分泌的 从培养的细胞和培养基中提取原胶原。 此外，主要 新生大鼠心脏成纤维细胞的培养物将被表征 关于前胶原的生物合成、分泌和 在培养物中“正常”增殖期间的细胞内降解， 并且在已知的多种药理学干预期间， 影响细胞培养系统中的胶原代谢。 最后， 环腺苷酸依赖的细胞内调节机制 “靶向”新合成的前胶原用于运输， 将检查成纤维细胞溶酶体内的降解。 如果 如果成功，这些研究将提供新的和重要的 关于心脏中胶原蛋白周转的基本信息 间质，并提供有用的实验工具， 该研究项目的其他研究人员对心脏病感兴趣， 间质胶原生物化学、细胞和分子生物学。