EMG activity of slow and fast ankle extensors following spinal cord transection.
EMG activity of slow and fast ankle extensors following spinal cord transection.
复制标题
脊髓横断后慢速和快速踝伸肌的肌电图活动。
DOI：
10.1152/jappl.1984.56.6.1608
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Edgerton,VR
中科院分区：
文献类型：
--
作者：
Alaimo,MA;Smith,JL;Roy,RR;Edgerton,VR
脊髓横断后慢缩纤维向快缩纤维的转变被认为与神经肌肉活动的实质性减少或实质性缺失有关。在本实验中，自发活动水平在脊髓和正常猫，提出了类似的条件下，综合肌电图（I-EMG）记录了240分钟超过24小时，从缓慢收缩的比目鱼肌（SOL）和快速收缩的外侧腓肠肌（LG）进行了评估。在脊髓损伤猫的SOL中，总I-EMG减少了75%，肌肉活动总持续时间减少了66%。相反，LG显示总I-EMG没有显着变化，但肌肉活动的总持续时间减少了66%。根据同伴研究中发表的肌肉特性数据，SOL总I-EMG与收缩时间减少或组织化学测定的慢缩纤维百分比减少之间没有显著相关性。我们的结论是，脊髓横断后慢缩纤维的转换可能受到几个因素的调节，其中之一是自发的日常活动的总水平。
Transformations of slow-twitch fibers to the fast-twitch type following spinal cord transection are thought to be related to a substantial decrease or virtual absence of neuromuscular activity. In this experiment, spontaneous activity levels in spinalized and normal cats, raised under similar conditions, were assessed by integrated electromyography (I-EMG) recorded for 240 min over 24 h from the slow-contracting soleus (SOL) and the fast-contracting lateral gastrocnemius (LG). In the SOL of the spinalized cats, there was a 75% reduction in total I-EMG and a 66% reduction in the total duration of muscle activity. Conversely, the LG showed no significant change in total I-EMG, but there was a 66% reduction in the total duration of muscle activity. Based on muscle property data published in companion studies, there was no significant correlation between the SOL total I-EMG and the reduction in contraction times or the decrease in the percentage of slow-twitch fibers determined histochemically. We conclude that transformations of slow-twitch fibers following spinal transection may be regulated by several factors, among which is the total level of spontaneous daily activity.