title: The frequencies of micronuclei induced by cisplatin in newborn rat astrocytes are increased by 50-Hz, 7.5- and 10-mT electromagnetic fields.
abstract: OBJECTIVE
  Epidemiological studies have suggested that exposure to environmental and occupational electromagnetic fields (EMFs) contribute to the induction of brain tumors, leukemia, and other neoplasms. The aim of this study was to investigate the genotoxic effects of exposure to 50-Hz EMFs. and of co-exposure to cisplatin, a mutagen and carcinogen, and 50-Hz EMFs, using an in vivo newborn rat astrocyte micronucleus assay.
  
  
  METHODS
  Three day-old male Sprague-Dawley rats were co-exposed to 50-Hz EMFs and 1.25 or 2.5 mg/kg of cisplatin. Brain cells were dissociated into single cells and cultured for 96 hours, then stained with acridine orange and an antibody against glial fibrillary acidic protein. The frequency of micronucleated astrocytes was counted with a fluorescent microscope.
  
  
  RESULTS
  The frequency of micronuclei was not increased in rat astrocytes exposed to EMFs alone. However, the frequencies of micronuclei in co-exposure to 2.5 mg/kg cisplatin and EMFs (7.5- and 10-mT) were significantly increased, compared with those in exposure to 2.5 mg/kg cisplatin alone (sham-exposure, 0-mT EMFs) for 72 hours (p<0.01).
  
  
  CONCLUSIONS
  Exposure to EMFs alone did not have a genotoxic effect but co-exposure to EMFs increased the genotoxic activity induced by cisplatin. Our findings suggest that EMFs enhance the genotoxic effects of cisplatin.
authors: Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, 3-25-8 Nishishinbashi, Minato-ku, 105-8461, Tokyo, Japan, miyakoshi@jikei.ac.jp.
authors: Yuichi
authors: Y
authors: Miyakoshi
authors: Hayato
authors: H
authors: Yoshioka
authors: Yoshimitsu
authors: Y
authors: Toyama
authors: Yuji
authors: Y
authors: Suzuki
authors: Hidesuke
authors: H
authors: Shimizu