BREATHING STRATEGY

特定呼吸肌的功能作用取决于 机械事件与神经事件的耦合。因为呼吸模式 可以很容易地调整，有人建议呼吸可以 调节以优化呼吸肌的效率。 在原位上，骨骼肌相对于其肌肉的工作长度 管理最优力产生长度(力长度特性) 通过主动张力，并发生在肌肉的长度是电的 活体内活跃。因此，在成年动物中，适应发生在肌肉中。 这样长度和激活最终将被同步 最优产量。 身体姿势的变化深刻地影响着关节的操作长度 呼吸肌。当姿势改变为举起(类似于坐在 清醒的动物)，横隔膜变短，如果没有补偿，将导致 由于长度-张力的考虑，潮气量减少。 然而，采用抬头姿势与 呼气肌的相当大的相位性招募(移位到 更有利的工作长度)，其机械贡献率为65% 在这个姿势下潮汐的体积。因此，用无效的头顶狗 横隔膜通过招募更有效的腹肌来进行补偿。 呼吸肌的机械性能与 他们的神经控制还没有得到研究。我们的假设是 呼吸肌的招募与他们的位置有关 考虑到它们的最佳长度。 拟议工作的目标是调查两者之间的关系 呼吸肌及其神经的机械效率 正常成年犬的对照。此外，要研究两者之间的关系 这两个参数在过渡状态下，呼吸策略是 新生动物和肺气肿动物(即，两者都代表条件 在操作长度发生适应的情况下)也将被调查。 这些研究应该在呼吸肌之间建立新的联系 机械学和呼吸控制。

The functional role of a particular respiratory muscle depends on the coupling of mechanical to neural events. Because the respiratory pattern can be easily adjusted, it has been suggested that respiration can be regulated to optimize the efficiency of the respiratory muscles. In situ, the operating length of a skeletal muscle with respect to its optimal force producing length (force length characteristics) is governed by active tension and occurs at a length where the muscle is electrically active in vivo. Thus, in adult animals, adaptations take place in muscle length such that length and activation will eventually be synchronized for optimal output. Changes in body posture profoundly influence the operational length of the respiratory muscles. As posture is changed to held up (akin to sitting in awake animals), the diaphragm shortens, and if uncompensated, would result in a reduction in tidal volume due to length-tension considerations. However, the adoption of the head up posture is associated with a considerable phasic recruitment of the expiratory muscles (displaced to more favorable operating lengths), their mechanical contribution being 65% of tidal volume in this posture. Thus, head up dogs with ineffective diaphragms compensate by recruiting more effective abdominal muscles. The link between the mechanical properties of the respiratory muscles and their neural control has not been investigated. Our hypothesis is that recruitment of the respiratory muscles is related to their position with respect to their optimal length. The goals of the proposed work are to investigate the relationship between the mechanical efficiency of the respiratory muscles and their neural control in normal adult dogs. Moreover, to study the relationship between both parameters during a transitional state, the strategy of breathing is neonatal and emphysematous animals (i.e., both representing conditions where adaptations occur in operating length) will also be investigated. These studies should establish a new link between respiratory muscle mechanics and the control of breathing.