在降落过程中,预突触抑制不会调解降低的Soleus H-Reflex幅度
Kevin Soter1,2,3, Daniel Hahn2,4, Sidney Grosprêtre3,5
1School of Medicine and Surgery, Università Degli Studi di Milano-Bicocca, Milan, Italy.
Scandinavian journal of medicine & science in sports
|September 2, 2025
概括
降落后脊柱刺激能力降低,但前突触抑制不是原因. 这表明其他机制降低着陆后的H反射活动.
科学领域:
- 神经科学
- 生物力学
- 发动机控制
背景情况:
- 在降落后不久,脊柱激发能力通过H反射测量下降.
- 这种下降被认为是由于前突触抑制,但尚未得到证实.
研究的目的:
- 在降落着陆的飞行和着陆阶段,研究突触前抑制的作用.
- 确定降低着陆后H反射的机制.
主要方法:
- 十五名参与者进行了40厘米的降落.
- 使用外周神经刺激 (股骨和常见的神经) 来评估通过H-反射异名促进 (HHF) 和H-反射D1抑制 (HD1) 的前突触抑制.
- 在静止姿势,降落前 (PRE) 和降落后 (POST) 测量索勒斯H反射幅度,并将其正常化为最大M波 (Mmax).
主要成果:
- 与PRE着陆相比,Soleus H-反射 (H测试) 的POST着陆显著较小 (-8.5%Mmax,p=0.016).
- 在安静姿势时观察到预突触抑制 (HHF和HD1),但在PRE或POST着陆阶段没有.
- 在静止状态下促进和抑制模式的有效性,与在落地过程中它们的缺失形成对比,表明前突触抑制不负责POST着陆的H反射减弱.
结论:
- 观察到的POST降落降低的H反射不能归因于正在进行的前突触抑制.
- 运动神经元刺激性降低,而不是前突触抑制,可能是降落后脊柱刺激性观察到的原因.
- 需要进行进一步的研究,以阐明在降落期间和之后导致脊柱刺激性变化的具体机制.
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