Modeling the oscillation dynamics of activated airway smooth muscle strips
Modeling the oscillation dynamics of activated airway smooth muscle strips
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DOI：
10.1152/ajplung.00129.2005
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发表时间：
2005-11-01
影响因子：
4.9
通讯作者：
Lauzon, AM
中科院分区：
文献类型：
--
作者：
Bates, JHT;Lauzon, AM
当激活的气道平滑肌条被周期性拉伸时，它们表现出力长度环，其位置和形状随着拉伸的幅度和频率而变化很大。这种行为最近被归因于施加的拉伸和肌肉中肌动蛋白-肌球蛋白相互作用的数量之间的动态相互作用。然而，众所周知，平滑肌的被动流变特性对其力学性能有重要影响。因此，我们假设这些流变特性在激活平滑肌的力-长度动力学中起着重要作用。为了验证这一假设的合理性，我们开发了一个平滑肌条模型，该模型由一个力发生器和一个弹性组件串联组成。当力源服从双曲力-速度关系，串联弹性分量高度非线性时，通过调整弹性刚度和力生成，使峰值环力等于等距力，该模型预测了实际的稳态力-长度环。我们得出结论，气道平滑肌的动态行为可以在很大程度上归因于结缔组织流变学和收缩蛋白的力-速度行为之间的相互作用。
When strips of activated airway smooth muscle are stretched cyclically, they exhibit force-length loops that vary substantially in both position and shape with the amplitude and frequency of the stretch. This behavior has recently been ascribed to a dynamic interaction between the imposed stretch and the number of actin-myosin interactions in the muscle. However, it is well known that the passive rheological properties of smooth muscle have a major influence on its mechanical properties. We therefore hypothesized that these rheological properties play a significant role in the force-length dynamics of activated smooth muscle. To test the plausibility of this hypothesis, we developed a model of the smooth muscle strip consisting of a force generator in series with an elastic component. Realistic steady-state force-length loops are predicted by the model when the force generator obeys a hyperbolic force-velocity relationship, the series elastic component is highly nonlinear, and both elastic stiffness and force generation are adjusted so that peak loop force equals isometric force. We conclude that the dynamic behavior of airway smooth muscle can be ascribed in large part to an interaction between connective tissue rheology and the force-velocity behavior of contractile proteins.