title: Effects of 50 Hz magnetic field exposure on the stress marker α-amylase in the rat mammary gland.
abstract: OBJECTIVE
  Concerns about adverse health effects of environmental exposure to 50/60 Hz magnetic fields (MF) have initiated numerous studies on laboratory animals with varying outcomes. Previously, we reported that rat strains responded differently to MF regarding mammary cell proliferation and tumor development indicating that (epi)genetic factors might influence MF effects in the breast tissue, yet without any identified mechanism. In the present study, α-amylase, recently introduced as a stress marker in humans, was investigated in the mammary gland of Fischer 344 (F344) and Lewis rats, two strains with distinct stress sensitivity.
  
  
  METHODS
  F344 rats were sham- and MF-exposed (50 Hz, 100 μT) for different time periods, Lewis rats for two weeks. For comparison, diethylstilbestrol was administered at single or repeated doses.
  
  
  RESULTS
  α-Amylase activity was significantly enhanced in the F344 mammary glands after 2 and 4 weeks of MF, whereas no reproducible effects were observed in Lewis rats. Diethylstilbestrol increased the α-amylase after repeated dosing.
  
  
  CONCLUSIONS
  Although α-amylase represents a difficult parameter in animal studies because of its stress sensitivity, it should be considered for investigations in humans and cell cultures as a biomarker for MF susceptibility and a target to examine possible MF mechanisms since α-amylase affects cell growth.
authors.affiliation: Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany. Maren.Fedrowitz@tiho-hannover.de
authors.forename: Maren
authors.initials: M
authors.lastname: Fedrowitz
authors.forename: Ralf
authors.initials: R
authors.lastname: Hass
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Löscher
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D005260:Female; D008321:Mammary Glands, Animal / Q000378:metabolism* / Q000528:radiation effects*; D011829:Radiation Dosage; D051381:Rats; D011916:Rats, Inbred F344; D013312:Stress, Physiological / Q000502:physiology* / Q000528:radiation effects*; D014018:Tissue Distribution; D000516:alpha-Amylases / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D000516:alpha-Amylases