title: [Effects of extremely low magnetic field on acute and chronic arthritis of rats].
abstract: OBJECTIVE
  To investigate the effects of extremely low magnetic field on acute and chronic arthritis of rats.
  
  
  METHODS
  The acute arthritis animal models were built by the right thenar hypodermic injection of carrageenan. Then they were exposed to magnetic field for 6 hours and 8 hours, respectively. The chronic arthritis animal models were built by the right thenar hypodermic injection of complete freund's adjuvant. They were exposed to magnetic field for 7 days and 6 hours each day after the secondary affection appeared 15 days later. The swelling and inflammatory cytokine were observed in both the acute and chronic arthritis models.
  
  
  RESULTS
  The ankle and thenar swellings decreased in both the acute and chronic arthritis models after different time exposure. The cytokine of serum and articular lixivium did not change in 6 hours exposed groups of acute arthritis models. The serum IL-6 and articular lixivium IL-6, TNF-alpha decreased compared with sham groups. Though the rest indexes were unchanged, they had the tendency of decrease.
  
  
  CONCLUSIONS
  The extremely low magnetic field has the effects of restraining acute and chronic arthritis of rats, and can also partially restrain the cytokines when the rats were exposed for 8 hours. The mechanisms need to be further investigated.
authors.affiliation: Bioelectromagnetics Lab, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Xiu-Qi
authors.initials: XQ
authors.lastname: Bao
authors.forename: Yi-Jun
authors.initials: YJ
authors.lastname: Shi
authors.forename: Yu-Xia
authors.initials: YX
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.forename: Tao
authors.initials: T
authors.lastname: Song
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000378:metabolism* / Q000473:pathology*; D004195:Disease Models, Animal; D004487:Edema / Q000517:prevention & control; D005620:Freund's Adjuvant / Q000009:adverse effects; D015850:Interleukin-6 / Q000378:metabolism; D060526:Magnetic Fields; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D005620:Freund's Adjuvant