Comparison of the depression of H-reflexes following previous activation in upper and lower limb muscles in human subjects
Comparison of the depression of H-reflexes following previous activation in upper and lower limb muscles in human subjects
复制标题
人类受试者上肢和下肢肌肉先前激活后 H 反射抑制的比较
DOI：
10.1007/s002210050721
复制
发表时间：
1999
影响因子：
2
通讯作者：
P. Bawa
中科院分区：
文献类型：
--
作者：
C. Rossi‐Durand;K. Jones;Simon Adams;P. Bawa
当条件反射（C-T）刺激作用于Ia传入引起h反射时，测试反射在条件反射之后立即消失。随着C-T间隔的增加，测试响应开始缓慢恢复，需要几百毫秒才能达到控制值。这种恢复的时间过程被称为h反射恢复曲线。采用表面肌电图和单运动单元活动对7名健康人下肢比目鱼肌和上肢桡腕屈肌的H反射恢复曲线进行了比较。休息条件下，比目鱼h反射和单运动单元活动恢复较慢；即使在2005年，复苏也没有完全完成。相比之下，FCR运动单元的恢复非常快，在200-300 ms内发生。同时研究了0.1-10.0 imp/s的刺激速率对h反射的影响。反射反应随刺激率的增加而下降，比目鱼肌的下降略大于FCR。在脊髓自愿促进下观察这些现象时，恢复时间缩短，刺激率的作用也减弱。FCR的背景促进变化大于比目鱼。这两种肌肉之间的差异主要归因于两个脊髓节段突触前抑制的差异，和/或与慢比目鱼肌运动神经元突触和与快速FCR运动神经元突触的Ia传入神经末端的递质释放动力学的差异。
Abstract When conditioning-testing (C-T) stimuli are applied to Ia afferents to elicit H-reflexes, the test reflex is abolished immediately following the conditioning reflex. As the C-T interval is increased, the test response slowly begins to recover, taking several hundred milliseconds to attain control values. The time course of this recovery is known as the H-reflex recovery curve. H- reflex recovery curves were compared using surface EMG and single motor unit activities in lower limb soleus and upper limb flexor carpi radialis (FCR) muscles in seven healthy human subjects. Under rest conditions, the recovery of H-reflexes and single motor unit activity was slow for soleus; the recovery was not complete even in 1 s. In comparison, the recovery was very fast for FCR motor units, occurring in 200–300 ms. The effects of rate of stimulation (0.1–10.0 imp/s) were also examined on the magnitude of H-reflex responses. The reflex response declined with increasing rate of stimulation, the decline being slightly greater in soleus than in FCR. When these phenomena were examined with voluntary facilitation of the spinal cord, the time of recovery shortened and the effect of stimulus rate also diminished. Changes with background facilitation were greater in FCR than in soleus. The differences between the two muscles are attributed mainly to differences in presynaptic inhibition in the two spinal segments, and/or to the differences in dynamics of the transmitter release in terminals of Ia afferents synapsing with slow soleus motoneurons and those synapsing with the fast FCR motoneurons.
DOI：
10.1016/0168-5597(93)90131-8
发表时间：
1993-06-01
期刊：
ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY
影响因子：
--
作者：
CALANCIE, B;BROTON, JG;AYYAR, DR
通讯作者：
AYYAR, DR
运动神经元特性及其突触输入的逆行测定。
DOI：
10.1002/neu.480250610
发表时间：
1994
期刊：
Journal of neurobiology
影响因子：
--
作者：
Mendell,LM;Collins3rd,WF;Munson,JB
通讯作者：
Munson,JB