title: Microwave exposure impairs synaptic plasticity in the rat hippocampus and PC12 cells through over-activation of the NMDA receptor signaling pathway.
abstract: OBJECTIVE
  The aim of this study is to investigate whether microwave exposure would affect the N-methyl-D-aspartate receptor (NMDAR) signaling pathway to establish whether this plays a role in synaptic plasticity impairment.
  
  
  METHODS
  48 male Wistar rats were exposed to 30 mW/cm2 microwave for 10 min every other day for three times. Hippocampal structure was observed through H&E staining and transmission electron microscope. PC12 cells were exposed to 30 mW/cm2 microwave for 5 min and the synapse morphology was visualized with scanning electron microscope and atomic force microscope. The release of amino acid neurotransmitters and calcium influx were detected. The expressions of several key NMDAR signaling molecules were evaluated.
  
  
  RESULTS
  Microwave exposure caused injury in rat hippocampal structure and PC12 cells, especially the structure and quantity of synapses. The ratio of glutamic acid and gamma-aminobutyric acid neurotransmitters was increased and the intracellular calcium level was elevated in PC12 cells. A significant change in NMDAR subunits (NR1, NR2A, and NR2B) and related signaling molecules (Ca2+/calmodulin-dependent kinase II gamma and phosphorylated cAMP-response element binding protein) were examined.
  
  
  CONCLUSIONS
  30 mW/cm2 microwave exposure resulted in alterations of synaptic structure, amino acid neurotransmitter release and calcium influx. NMDAR signaling molecules were closely associated with impaired synaptic plasticity.
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xiong
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Cheng Feng
authors.initials: CF
authors.lastname: Sun
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Ya Bing
authors.initials: YB
authors.lastname: Gao
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Li Feng
authors.initials: LF
authors.lastname: Wang
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Hong Yan
authors.initials: HY
authors.lastname: Zuo
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Shui Ming
authors.initials: SM
authors.lastname: Wang
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Hong Mei
authors.initials: HM
authors.lastname: Zhou
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Xin Ping
authors.initials: XP
authors.lastname: Xu
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Dong
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Bin Wei
authors.initials: BW
authors.lastname: Yao
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Rui Yun
authors.initials: RY
authors.lastname: Peng
mesh_terms: D000818:Animals; D005786:Gene Expression Regulation / Q000528:radiation effects; D006624:Hippocampus / Q000166:cytology*; D008872:Microwaves; D009473:Neuronal Plasticity / Q000528:radiation effects*; D009474:Neurons / Q000528:radiation effects*; D018377:Neurotransmitter Agents / Q000378:metabolism; D016716:PC12 Cells; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology / Q000528:radiation effects*; D013997:Time Factors
chemical_list: D018377:Neurotransmitter Agents; D016194:Receptors, N-Methyl-D-Aspartate
keywords: Microwave; NMDA receptor signaling pathway; PC12; Rat hippocampus; Synaptic plasticity