MYOCARDIAL SARCOMERE MECHANICS

心肌肌节力学

• 批准号: 3335659
• 负责人: GERALD H POLLACK
• 金额: $ 17.77万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-04-01 至 1991-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3335659
• 关键词: Anura; biomechanics; heart contraction; heart disorder; laboratory rat; lasers; mechanical pressure; molecular pathology; muscle tension; myofibrils; myosins; sarcomeres

Our aim is to continue studies of the mechanics of the heart. We have been interested in the dynamics of contraction, the long-term goal being to relate properties at the sarcomere and molecular level to contraction in the myocardium. The present experiments, in particular, are designed to explore the implications of stepwise shortening. We have found that shortening occurs in discrete steps, synchronized over a large region of space and punctuated by pauses. This is unexpected according to current ideas about the contractile process; yet we have now confirmed it by four independent methods. Among the questions we wish to answer are: (1) Do steps occur in single myofibrillar sarcomers? (2) Is myosin critical for the presence of stepwise shortening? (3) Is step size quantized? (4) What is the mechanism of synchrony? (5) Does the pause precede the step, or vice-versa? (6) What is the role of activation? These questions will be answered using state of the art sensors to measure sarcomere and segment dynamics.

我们的目标是继续研究心脏的力学。 我们曾经 对收缩的动态感兴趣，长期目标是 将肌节和分子水平的特性与收缩联系起来 心肌。 本实验尤其旨在 探索逐步缩短的含义。 我们发现 缩短发生在离散步骤中，在大范围内同步 空间并被停顿所打断。 根据目前的情况来看，这是出乎意料的 关于收缩过程的想法；但我们现在已经有四个人证实了这一点 独立的方法。 我们希望回答的问题包括： (1) 单个肌原纤维肌节发生步骤？ (2) 肌球蛋白对于 是否存在逐步缩短？ (3) 步长是否量化？ (4) 什么 是同步机制吗？ (5) 暂停是否在步骤之前，或者 反之亦然？ （6）激活的作用是什么？ 这些问题将会 使用最先进的传感器来测量肌节和节段来回答 动力学。