MOLECULAR AND CELLULAR BIOLOGY OF CARDIAC INTERSTITIUM

心脏间质的分子和细胞生物学

• 批准号: 3362241
• 负责人: Allen Mark Samarel
• 金额: $ 10.17万
• 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/3362241
• 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 体内胶原蛋白代谢的细胞内调控机制 正常和肥厚大鼠左室心肌，AS 原代培养的新生大鼠心脏成纤维细胞也是如此。 拟议的实验集中在一个特定的方面 胶原蛋白的代谢；即细胞内的退行性变 大鼠心脏成纤维细胞合成新的前胶原 体内和在细胞培养中。细胞内调控机制 这一重要的过程还没有得到充分的理解，潜在的 对于新药“靶向性”的药理调节 用于细胞内破坏的合成前胶原多肽 会提供另一种减少胶原蛋白堆积的方法 与间质相关的多种心血管疾病 纤维化症。具体的实验被概述以估计在体内 胶原蛋白生物合成、积累和降解的速率 大鼠左心室正常生理性生长过程中的变化 在甲状腺激素诱导的LV的形成过程中 腹主动脉后的肥厚和左室肥厚 缩水。特定的单抗探针也将被 为研究前胶原多肽代谢而开发 培养的新生大鼠心脏成纤维细胞。这些序列- 特异性单抗(针对 大鼠I型和III型前胶原蛋白的原氨基肽段 多肽)将用于特定的放射免疫分析 细胞内和分泌型前胶原的定量分析， 以及免疫吸附剂的生产 新合成和分泌物的定量分离 培养细胞和培养液中的原胶原。此外，主要的 新生大鼠心脏成纤维细胞的培养将成为 关于前胶原的生物合成、分泌和 在培养的“正常”增殖过程中的细胞内降解， 以及在已知的各种药物干预期间 影响细胞培养系统中的胶原蛋白代谢。最后， 环磷酸腺苷依赖的细胞内调控机制 新合成的前胶原在运输和运输中的“靶向性” 将检查成纤维细胞溶酶体内的降解情况。如果 成功，这些研究应该提供新的和重要的 心脏胶原代谢的基本信息 并提供了有用的实验工具 这个研究项目中的其他研究人员对心脏 间质胶原生物化学、细胞和分子生物学。