Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, Kita 12 Nishi 5, Kita-ku, Sapporo 060-0812, Japan.
Research Fellow of Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan; Graduate School of Health Sciences, Hokkaido University, Kita 12 Nishi 5, Kita-ku, Sapporo 060-0812, Japan.
Neurosci Lett. 2021 May 14;753:135864. doi: 10.1016/j.neulet.2021.135864. Epub 2021 Apr 1.
Transcranial static magnetic field stimulation (tSMS) has inhibitory neuromodulatory effects on the human brain. Most of the studies on static magnetic fields have been performed in vitro. To further understand the biological mechanisms of tSMS, we investigated the effects of in vivo tSMS on motor behavior in normal awake rats. The skull of a male Wistar rat was exposed and a polyethylene tube was attached to the skull using dental cement at the center of the motor cortex (n = 7) or the other cortex (n = 6). By attaching a cylindrical NdFeB neodymium magnet into the tube, in vivo tSMS (REAL) was performed. For SHAM, we applied a similar size non-magnetic stainless-steel cylinder. All rats received twice each SHAM and REAL stimulation every two days using a crossover design, and motor function was measured during the stimulation. Activity level and asymmetry of forelimb use were not affected, but less accurate movements in the horizontal ladder test were found in REAL stimulation of the motor cortex. This study shows that in vivo tSMS has inhibitory neuromodulatory effects on motor behavior depending on the stimulated region on the rat cortex.
经颅静磁场刺激（tSMS）对人脑具有抑制性神经调节作用。大多数关于静磁场的研究都是在体外进行的。为了进一步了解 tSMS 的生物学机制，我们研究了体内 tSMS 对正常清醒大鼠运动行为的影响。雄性 Wistar 大鼠的颅骨暴露，在运动皮层中心（n=7）或其他皮层（n=6）用牙科水泥将聚乙烯管固定在颅骨上。通过将圆柱形 NdFeB 钕磁铁附着在管中，进行体内 tSMS（REAL）。对于 SHAM，我们使用了类似大小的非磁性不锈钢圆柱。所有大鼠均采用交叉设计，每两天接受两次 SHAM 和 REAL 刺激，在刺激过程中测量运动功能。活动水平和前肢使用的不对称性没有受到影响，但在运动皮层的 REAL 刺激中发现水平梯测试的动作准确性降低。这项研究表明，体内 tSMS 对大鼠皮层受刺激区域的运动行为具有抑制性神经调节作用。
