title: Circadian rhythmicity of antioxidant markers in rats exposed to 1.8 GHz radiofrequency fields.
abstract: BACKGROUND
  The potential health risks of exposure to Radiofrequency Fields (RF) emitted by mobile phones are currently of considerable public interest, such as the adverse effects on the circadian rhythmicities of biological systems. To determine whether circadian rhythms of the plasma antioxidants (Mel, GSH-Px and SOD) are affected by RF, we performed a study on male Sprague Dawley rats exposed to the 1.8 GHz RF.
  
  
  METHODS
  All animals were divided into seven groups. The animals in six groups were exposed to 1.8 GHz RF (201.7 μW/cm² power density, 0.05653 W/kg specific absorption rate) at a specific period of the day (3, 7, 11, 15, 19 and 23 h GMT, respectively), for 2 h/day for 32 consecutive days. The rats in the seventh group were used as sham-exposed controls. At the end of last RF exposure, blood samples were collected from each rat every 4 h (total period of 24 h) and also at similar times from sham-exposed animals. The concentrations of three antioxidants (Mel, GSH-Px and SOD) were determined. The data in RF-exposed rats were compared with those in sham-exposed animals.
  
  
  RESULTS
  circadian rhythms in the synthesis of Mel and antioxidant enzymes, GSH-Px and SOD, were shifted in RF-exposed rats compared to sham-exposed animals: the Mel, GSH-Px and SOD levels were significantly decreased when RF exposure was given at 23 and 3 h GMT.
  
  
  CONCLUSIONS
  The overall results indicate that there may be adverse effects of RF exposure on antioxidant function, in terms of both the daily antioxidative levels, as well as the circadian rhythmicity.
authors: School of Electronic & Information Engineering, Soochow University, Suzhou 215006, China. caohonglong@suda.edu.cn.
authors: Honglong
authors: H
authors: Cao
authors: Department of Biological Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, China. qinfenju@163.com.
authors: Fenju
authors: F
authors: Qin
authors: School of Electronic & Information Engineering, Soochow University, Suzhou 215006, China. txdzlxg@suda.edu.cn.
authors: Xueguan
authors: X
authors: Liu
authors: School of Electronic & Information Engineering, Soochow University, Suzhou 215006, China. jjwang@suda.edu.cn.
authors: Jiajun
authors: J
authors: Wang
authors: School of Public Health, Medical College of Soochow University, Suzhou 215123, China. yicao@suda.edu.cn.
authors: Yi
authors: Y
authors: Cao
authors: School of Public Health, Medical College of Soochow University, Suzhou 215123, China. tongjian@suda.edu.cn.
authors: Jian
authors: J
authors: Tong
authors: School of Electronic & Information Engineering, Soochow University, Suzhou 215006, China. hmzhao@suda.edu.cn.
authors: Heming
authors: H
authors: Zhao
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D015415:Biomarkers; D040421:Cell Phone; D002940:Circadian Rhythm; D008297:Male; D011846:Radio Waves / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000975:Antioxidants; D015415:Biomarkers