Mancheva Kapka, Schrader Christoph, Christova Lilia, Dengler Reinhard, Kossev Andon R
Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, "Acad. G. Bonchev" Str., bl. 21, 1113, Sofia, Bulgaria.
Eur J Appl Physiol. 2014 Oct;114(10):2073-80. doi: 10.1007/s00421-014-2930-x. Epub 2014 Jun 17.
The purpose of the present study was to investigate the effect of muscle vibration (MV) on short latency intracortical inhibition (SICI) and facilitation (ICF) assessed by paired-pulse transcranial magnetic stimulation (TMS).
Nineteen right-handed healthy subjects were investigat ed without and with MV of the right extensor carpi radialis (ECR), using single- and paired-pulse TMS with interstimulus interval (ISI) of 3 and 13 ms. Intensities of the conditioning and test stimulus were 70 and 120 % of the motor threshold at rest. The motor-evoked potentials (MEPs) were recorded simultaneously from the vibrated ECR and its antagonist flexor carpi radialis (FCR).
In all the subjects a SICI of similar strength could be observed at 3 ms, at rest and during MV both in the vibrated muscle as well as in its antagonist. The subjects were divided in two groups according to the changes in MEP response to paired-pulse TMS with 13 ms ISI observed during MV. In nine subjects SICI was evident also at 13 ms when vibration was applied, while in another ten subjects vibration induced ICF at 13 ms.
The effect of MV is not just a facilitation of SICI, but a stronger prolongation of the effect of intracortical inhibition to an ISI at which ICF is well pronounced, when the intensity of the conditioning stimulus exceeds the threshold for intracortical facilitation.
本研究旨在探讨肌肉振动（MV）对通过配对脉冲经颅磁刺激（TMS）评估的短潜伏期皮质内抑制（SICI）和易化（ICF）的影响。
19名右利手健康受试者在右侧桡侧腕伸肌（ECR）不进行和进行MV的情况下接受研究，使用刺激间隔（ISI）为3毫秒和13毫秒的单脉冲和配对脉冲TMS。条件刺激和测试刺激的强度分别为静息时运动阈值的70%和120%。同时从振动的ECR及其拮抗肌桡侧腕屈肌（FCR）记录运动诱发电位（MEP）。
在所有受试者中，在3毫秒时，无论静息还是MV期间，在振动肌肉及其拮抗肌中均可观察到强度相似的SICI。根据MV期间观察到的对ISI为13毫秒的配对脉冲TMS的MEP反应变化，将受试者分为两组。9名受试者在施加振动时13毫秒时SICI也很明显，而在另外10名受试者中，振动在13毫秒时诱发了ICF。
MV的作用不仅是促进SICI，而且当条件刺激强度超过皮质内易化阈值时，会使皮质内抑制作用更强地延长至ICF明显的ISI。
