title: Extremely low-frequency magnetic fields modulate nitric oxide signaling in rat brain.
abstract: Our previous study has shown that an extremely low-frequency magnetic field (ELF-MF) induces nitric oxide (NO) synthesis by Ca(2+) -dependent NO synthase (NOS) in rat brain. The present study was designed to confirm that ELF-MF affects neuronal NOS (nNOS) in several brain regions and to investigate the correlation between NO and nNOS activation. The exposure of rats to a 2 mT, 60 Hz ELF-MF for 5 days resulted in increases of NO levels in parallel with cGMP elevations in the cerebral cortex, striatum, and hippocampus. Cresyl violet staining and electron microscopic evaluation revealed that there were no significant differences in the morphology and number of neurons in the cerebral cortex, striatum, and hippocampus. Differently, the numbers of nNOS-immunoreactive (IR) neurons were significantly increased in those cerebral areas in ELF-MF-exposed rats. These data suggest that the increase in NO could be due to the increased expression and activation of nNOS in cells. Based on NO signaling in physiological and pathological states, ELF-MF created by electric power systems may induce various physiological changes in modern life.
authors.affiliation: Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul, Korea.
authors.forename: Sung In
authors.initials: SI
authors.lastname: Cho
authors.forename: Yun Sung
authors.initials: YS
authors.lastname: Nam
authors.forename: Li Ying
authors.initials: LY
authors.lastname: Chu
authors.forename: Jong Hyuk
authors.initials: JH
authors.lastname: Lee
authors.forename: Joon Seok
authors.initials: JS
authors.lastname: Bang
authors.forename: Hye Ryoun
authors.initials: HR
authors.lastname: Kim
authors.forename: Hyoung-Chun
authors.initials: HC
authors.lastname: Kim
authors.forename: Yu Jeung
authors.initials: YJ
authors.lastname: Lee
authors.forename: Hyeong-Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Jung Duk
authors.initials: JD
authors.lastname: Sul
authors.forename: Daejin
authors.initials: D
authors.lastname: Kim
authors.forename: Yoon Hee
authors.initials: YH
authors.lastname: Chung
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Jeong
mesh_terms: D000818:Animals; D048588:Benzoxazines / Q000378:metabolism; D001921:Brain / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects* / Q000648:ultrastructure; D006152:Cyclic GMP / Q000378:metabolism; D003720:Densitometry; D004574:Electromagnetic Fields / Q000009:adverse effects*; D008297:Male; D008854:Microscopy, Electron; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000528:radiation effects*
chemical_list: D048588:Benzoxazines; C028911:cresyl violet; D009569:Nitric Oxide; D006152:Cyclic GMP