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突触动力学与在肌性侧面硬化症中外周无神经之前广泛升高的H反射有关
Sina Sangari1,2,3, Alexandra Lackmy-Vallee1, Arnaud Preuilh1
1INSERM, CNRS, Laboratoire d'Imagerie Biomédicale (LIB), Sorbonne Université, Paris, France.
Journal of neurophysiology
|October 16, 2024
概括
霍夫曼反射 (H-反射) 在大多数肌肉中增加,不论疾病发作. 这种H反射增强可能表明抑制控制减少,并在临床试验中作为金字塔功能障碍的生物标志物.
科学领域:
- 神经科学是一个神经科学.
- 神经学 神经学
- 运动神经元疾病 运动神经元疾病
背景情况:
- 肌缩性侧面硬化症 (ALS) 呈现异质的表型,导致各种霍夫曼反射 (H-反射) 变化.
- 目前关于ALS中H反射的研究主要是检查肌底肌肉,可能会忽视更广泛的模式.
研究的目的:
- 为了研究ALS患者多个肌肉 (足底,四头肌,前臂 flexors) 的H反射变化.
- 为了将H-反射变化与ALS患者表型相关联,包括发病地点和功能障碍.
- 探索ALS中H反射修饰的基础的神经生理机制.
主要方法:
- 在ALS患者和对照人群之间比较H-反射招募曲线的单体,四头肌和前臂曲器.
- 评估四头肌中的H反射和运动唤起潜力 (MEP) 招募曲线.
- 对单个运动单元活动 (PSTH,PSF) 和对脉冲H反射进行分析,以评估突触变化.
主要成果:
- 在ALS患者的所有测试肌肉中,最大的H反射与直接运动反应振幅比率增加,无论疾病发作如何.
- 这种H反射增强与夸张的骨突反射和性正相关,并被riluzole减少.
- MEP 尺寸下降,而 PSTH,PSF 和对脉冲 H 反射概率保持不变,这表明单突触刺激保留但抑制控制减少.
结论:
- H-反射增强在ALS中是一种广泛的现象,不受疾病发病地点的限制,并且可能源于对脊柱运动神经元的抑制控制降低.
- 虽然其在识别金字塔综合征中的作用有限,但H反射的定量性质使其成为评估ALS临床试验中金字塔功能障碍的有价值生物标志物.
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