title: Repetitive transcranial magnetic stimulation enhances spatial learning and synaptic plasticity via the VEGF and BDNF-NMDAR pathways in a rat model of vascular dementia.
abstract: This study aimed to evaluate the effects of repetitive transcranial magnetic stimulation (rTMS) on learning and memory in a rat model of vascular dementia (VaD) and to analyze the associated mechanisms. Bilateral carotid artery occlusion (2-VO) was used to establish a rat model of VaD. High-frequency (5Hz) rTMS was performed on rats for four weeks. Spatial learning and memory abilities were evaluated using the Morris water maze (MWM), and synaptic plasticity in the hippocampus was assessed via long-term potentiation (LTP). Hippocampal expression of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF) and three subunits of the N-methyl-D-aspartic acid receptor (NMDAR), NR1, NR2A and NR2B, was analyzed by Western blotting. Compared with the VaD group, escape latency was decreased (P<0.05) and the time spent in the target quadrant and the percentage of swimming distance within that quadrant were increased (P<0.05) in the rTMS group. LTP at hippocampal CA3-CA1 synapses was enhanced by rTMS (P<0.05). VEGF expression was up-regulated following 2-VO and was further increased by rTMS (P<0.05). BDNF, NR1 and NR2B expression was decreased in the VaD group and increased by rTMS (P<0.05). There were no significant differences in NR2A expression among the three groups. These results suggest that rTMS improved learning and memory in the VaD model rats via the up-regulation of VEGF, BDNF and NMDARs. In addition, NR2B may be more important than NR2A for LTP induction in the hippocampus during rTMS treatment of VaD.
authors.affiliation: Department of Neurology, Key Laboratory of Post-Traumatic Neuro-Repair and Regeneration in the Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: N
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Neurology, Key Laboratory of Post-Traumatic Neuro-Repair and Regeneration in the Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: M
authors.initials: M
authors.lastname: Xing
authors.affiliation: Department of Neurology, Tianjin Haihe Hospital, Tianjin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Neurology, Key Laboratory of Post-Traumatic Neuro-Repair and Regeneration in the Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: H
authors.initials: H
authors.lastname: Tao
authors.affiliation: Department of Neurology, Key Laboratory of Post-Traumatic Neuro-Repair and Regeneration in the Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China. Electronic address: cy_lfl@163.com.
authors.forename: Y
authors.initials: Y
authors.lastname: Cheng
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D015140:Dementia, Vascular / Q000503:physiopathology* / Q000523:psychology / Q000628:therapy*; D004195:Disease Models, Animal; D006624:Hippocampus / Q000503:physiopathology; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D065853:Spatial Learning / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D016194:Receptors, N-Methyl-D-Aspartate; D042461:Vascular Endothelial Growth Factor A; C409466:NR1 NMDA receptor; C121001:NR2B NMDA receptor; C467498:vascular endothelial growth factor A, rat
keywords: BDNF; N-methyl-d-aspartic acid receptor; VEGF; long-term potentiation; repetitive transcranial magnetic stimulation; vascular dementia