Beom Jaewon, Lee Jung Chan, Paeng Jin Chul, Han Tai Ryoon, Bang Moon Suk, Oh Byung-Mo
Department of Rehabilitation Medicine, Chungnam National University Hospital, Daejeon; Department of Biomedical Engineering, Seoul National University College of Medicine.
Department of Biomedical Engineering, Seoul National University College of Medicine; Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University; Department of Biomedical Engineering, Seoul National University Hospital.
J Vis Exp. 2016 Oct 22(116):54217. doi: 10.3791/54217.
Previous rodent models of repetitive transcranial magnetic stimulation (rTMS) adopted whole-brain stimulation instead of unilateral hemispheric rTMS, which is unlike the protocols used for human subjects. We report a successful application of rTMS to the unilateral hemisphere of rat brain. The rTMS was delivered with a low-frequency (1 Hz), high-frequency (20 Hz), or sham stimulation protocol to one side of the brain by using a small 25-mm figure-8 coil. We placed the center of the coil 1 cm lateral to the vertex on the biauricular line and angulated the coil 45° to the ground to minimize a potential direct effect of rTMS on the contralateral cortex. We also used an in-house water cooling system to enable repetitive magnetic stimulation for more than 20 min, even at a 20-Hz stimulation frequency. Increases in the transcriptions of immediate early genes (Arc, Junb, and Egr2) were greater after rTMS than after sham stimulation. After 5 consecutive days of 20-min 1-Hz rTMS, bdnf mRNA expression was significantly higher in stimulated cortex than in contralateral side. The model presented herein will elucidate the molecular mechanisms of rTMS by allowing analysis of the inter-hemispheric difference in its effect.
以往的重复经颅磁刺激（rTMS）啮齿动物模型采用的是全脑刺激，而非单侧半球rTMS，这与用于人类受试者的方案不同。我们报告了rTMS在大鼠脑单侧半球的成功应用。通过使用一个25毫米的小型8字形线圈，以低频（1赫兹）、高频（20赫兹）或假刺激方案对脑的一侧进行rTMS。我们将线圈中心置于双耳线上顶点外侧1厘米处，并使线圈与地面成45°角，以尽量减少rTMS对侧皮质的潜在直接影响。我们还使用了一个内部水冷系统，即使在20赫兹的刺激频率下，也能进行超过20分钟的重复磁刺激。rTMS后即刻早期基因（Arc、Junb和Egr2）的转录增加比假刺激后更大。在连续5天每天进行20分钟的1赫兹rTMS后，受刺激皮质中的脑源性神经营养因子（bdnf）mRNA表达明显高于对侧。本文提出的模型将通过分析rTMS效应的半球间差异来阐明其分子机制。
