Functional Dopaminergic Neurons in Substantia Nigra are Required for Transcranial Magnetic Stimulation-Induced Motor Plasticity.
Repetitive magnetic stimulation (rTMS), including theta burst stimulation (TBS), is capable of modulating motor cortical excitability through plasticity-like mechanisms and might have therapeutic potential for Parkinson's disease (PD). An animal model would be helpful for elucidating the mechanism of rTMS that remain unclear and controversial. Here, we have established a TMS model in rat and applied this model to study the impact of substantia nigra dopamine neuron on TBS-induced motor plasticity in PD rats. In parallel with human results, continuous TBS (cTBS) successfully suppressed motor evoked potentials (MEPs), while MEPs increased after intermittent TBS (iTBS) in healthy rats. We then tested the effect of iTBS in early and advanced 6-hydroxydopamine (6-OHDA)-lesioned PD. Moreover, dopaminergic neurons in substantia nigra and rotation behavior were assessed to correlate with the amount of iTBS-induced plasticity. In results, iTBS-induced potentiation was reduced in early PD rats and was absent in advanced PD rats. Such reduction in plasticity strongly correlated with the dopaminergic cell loss and the count of rotation in PD rats. In conclusion, we have established a TMS PD rat model. With the help of this model, we confirmed the loss of domaninergic neurons in substantia nigra resulting in reduced rTMS-induced motor plasticity in PD.
Graduate Institute of Neural Regenerative Medicine Center for Neurotrauma and Neuroregeneration and Department of Biomedical Engineering and.
Tsung-Hsun
TH
Hsieh
Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taipei, Taiwan.
Ying-Zu
YZ
Huang
Department of Neurology, Boston Children's Hospital.
Alexander
A
Rotenberg
Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Alvaro
A
Pascual-Leone
Graduate Institute of Neural Regenerative Medicine Center for Neurotrauma and Neuroregeneration and Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan.
Yung-Hsiao
YH
Chiang
Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan.
Jia-Yi
JY
Wang
Department of Biomedical Engineering and Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
Jia-Jin J
JJ
Chen
D000818:Animals; D059290:Dopaminergic Neurons / Q000473:pathology / Q000502:physiology*; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000502:physiology / Q000503:physiopathology; D009473:Neuronal Plasticity / Q000502:physiology*; D016627:Oxidopamine; D020734:Parkinsonian Disorders / Q000473:pathology / Q000503:physiopathology; D017208:Rats, Wistar; D012720:Severity of Illness Index; D013378:Substantia Nigra / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
D016627:Oxidopamine
6-OHDA; Parkinson's disease; motor evoked potential; rat; theta burst stimulation