在肌缩侧面硬化症中,内在运动神经元兴奋性的纵向变化取决于疾病进展
Gabriel S Trajano1, Lucas B R Orssatto2, Pamela A McCombe3,4
1School of Exercise and Nutrition Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, Queensland, Australia.
The Journal of physiology
|September 28, 2023
概括
持续的向内流 (PICs) 最初在早期肌缩侧面硬化症 (ALS) 中增加强度,然后随着肌肉疲弱的进展而下降. 这项研究追踪了随着时间的推移,ALS患者的PIC贡献变化.
科学领域:
- 神经科学是一个神经科学.
- 运动神经元疾病研究研究
- 人体生理学 人体生理学
背景情况:
- 持续向内流 (PICs) 在肌缩侧面硬化症 (ALS) 的小鼠模型中显示变化的振幅,在症状前增加,在症状后减少.
- 对ALS中PIC的人类研究产生了相互矛盾的结果,需要进行纵向研究.
研究的目的:
- 调查ALS患者中PIC对运动神经元自主持续发射的贡献的纵向变化.
- 为了比较肌肉中的这些变化与不同程度的软弱.
主要方法:
- 利用配对运动单元分析计算了43名患有ALS的人大约17周内前肌的Δ频率 (ΔF).
- 在40%的最大容量下,在加快的背部屈曲收缩过程中记录了高密度电肌图.
- 使用ALSFRS-R得分评估临床状态.
主要成果:
- 在研究期间, ΔF 在较强的肌肉中增加 (从3.14到3.55 pps),但在较弱的肌肉中减少 (从3.38到2.88 pps).
- 观察到的ΔF变化与ALS的SOD1小鼠模型的发现一致.
- ALSFRS-R得分下降3.9分,表明疾病进展.
结论:
- 在肌肉衰弱明显之前,PIC对运动神经元发射的贡献最初会在早期的ALS阶段增加.
- 随着疾病的进展和肌肉软弱的恶化,PIC的贡献随后会减少.
- 这些发现提供了纵向人类数据,支持PIC在ALS进展中的动态变化.
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