在古怪的收缩过程中保存了哺乳动物肌肉机制
Roger W P Kissane1, Graham N Askew2
1Department of Musculoskeletal & Ageing Science, University of Liverpool, Liverpool, UK.
The Journal of physiology
|February 24, 2024
概括
骨架肌肉是一个骨肌肉.
科学领域:
- 生物力学 生物力学
- 肌肉生理学 肌肉生理学
- 哺乳动物的肌肉功能
背景情况:
- 骨肌肉的力-速度关系对于发电和能量吸收至关重要.
- 这种关系的异常 (延长) 组成部分在哺乳动物肌肉中不明.
- 对于异常肌肉行为的现有数学模型缺乏全面的数据.
研究的目的:
- 在四种不同的哺乳动物肌肉中全面评估同心和偏心的力-速度关系.
- 为了研究这些关系如何在广泛的肌肉质量和生物机械功能中变化.
- 为改善异常肌肉收缩的数学模型提供数据.
主要方法:
- 通过使用高压-线性 (集中) 和高压 (离心) 方程来表征力-速度关系.
- 测量了在等速延长坡道中力量发展的速度.
- 在小鼠,老鼠和子身上研究了soleus,扩展器digitorumlongus,腹膜和消化肌肉.
- 通过使用小鼠进行titin删除来研究titin的作用.
主要成果:
- 在活跃的肌肉延长过程中,在哺乳动物肌肉质量的三个数量级上证明了保存的双相力响应.
- 在等速延长坡道上发现了相对力发展的一致率,尽管异常力-速度曲线的变化.
- 显示titin激活影响肌肉延长期间的双相力概况.
结论:
- 异常收缩期间的双相力反应在各种哺乳动物肌肉和身体大小中保持不变.
- 蒂激活在异常力-速度关系中起作用.
- 肌肉伸展期间力量发展的速度是异常肌肉力量的可靠预测指标,可以告知Hill型模型.
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