MYOCARDIAL SARCOMERE MECHANICS

我们的目标是继续研究心脏的力学。 我们一直 对收缩的动力学感兴趣，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 特别是，本实验旨在 探索逐步缩短的含义。 我们发现 缩短以离散的步骤发生，在一个大的区域上同步， 间隔和被停顿打断。 这是出乎意料的，根据目前 关于收缩过程的想法;然而，我们现在已经证实了四个 独立的方法。 我们希望回答的问题包括：（1） 步骤发生在单个肌原纤维肌角？ (2)肌球蛋白对于 逐步缩短的存在吗 (3)步长是否量化？ (4)什么 是同步的机制 (5)停顿是在步骤之前，还是 反之亦然 (6)激活的作用是什么？ 这些问题将 使用最先进的传感器测量肌节和节段 动力学

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.