An action potential-driven model of soleus muscle activation dynamics for locomotor-like movements.
An action potential-driven model of soleus muscle activation dynamics for locomotor-like movements.
复制标题
DOI：
10.1088/1741-2560/12/4/046025
复制
发表时间：
2015-08
影响因子：
4
通讯作者：
Heckman CJ
中科院分区：
文献类型：
--
作者：
Kim H;Sandercock TG;Heckman CJ
本研究的目标是为生理相关的激励和运动下的肌肉激活动力学 (A(t)) 开发一个生理上合理、计算稳健的模型。通过比较猫比目鱼肌及其 Hill 型模型之间的力产生，研究了 A(t) 上的激励和运动的相互作用。为了捕获激励和运动变化下的 A(t)，提出了一个模块化建模框架，该框架由 3 个部分组成：(1) 尖峰到 [Ca2+]； (2) [Ca2+]-至-A； (3)A到力的转换。基于生理因素对各个信号转换进行建模，以便可以直接根据实验数据单独确定各个模块的参数值。在等长收缩和动态运动收缩期间都发现 A(t) 对激励频率和肌肉长度的强烈依赖性。通过将模型参数调制为运动输入的函数，可以将静态和动态条件下确定的 A(t) 依赖性合并到模块化建模框架中。新的建模方法也适用于猫比目鱼肌，其产生的波形与用于设置模型参数的波形无关。这项研究为运动过程中尖峰驱动的肌肉反应提供了一个建模框架，该框架不仅适合深入了解肌肉行为背后的分子机制，而且适合大规模模拟。
The goal of this study was to develop a physiologically plausible, computationally robust model for the muscle activation dynamics (A(t)) under physiologically relevant excitation and movement. The interaction of excitation and movement on A(t) was investigated comparing the force production between a cat soleus muscle and its Hill-type model. For capturing A(t) under excitation and movement variation, a modular modeling framework was proposed comprising of 3 compartments: (1) spikes-to-[Ca2+]; (2) [Ca2+]-to-A; and (3) A-to-force transformation. The individual signal transformations were modeled based on physiological factors so that the parameter values could be separately determined for individual modules directly based on experimental data. The strong dependency of A(t) on excitation frequency and muscle length was found during both isometric and dynamically-moving contractions. The identified dependencies of A(t) under the static and dynamic conditions could be incorporated in the modular modeling framework by modulating the model parameters as a function of movement input. The new modeling approach was also applicable to cat soleus muscles producing waveforms independent of those used to set the model parameters. This study provides a modeling framework for spike-driven muscle responses during movement, that is suitable not only for insights into molecular mechanisms underlying muscle behaviors but also for large scale simulations.