title: Histological characteristics of cutaneous and thyroid mast cell populations in male rats exposed to power-frequency electromagnetic fields.
abstract: OBJECTIVE
  The objective of this study was to determine whether mast cells (MC) in skin and thyroid gland, cutaneous nerve fibers and eosinophils are sensitive to the influence of electromagnetic fields (EMF).
  
  
  METHODS
  The experiment was performed on two-month-old Wistar male rats, exposed to 50 Hz EMF (100-300 microT, 54-160 V/m) for 4 h a day, seven days a week during one month. After sacrifice, samples of skin and thyroid were processed for toluidine blue staining or indirect immunohistochemistry. The M42 grid placed in the ocular of a light microscope and a special microscopic frame placed in the ocular of a fluorescence microscope were used for stereological analysis.
  
  
  RESULTS
  The numerical and volume density of intact type A MC in the thyroid of the exposed group was significantly higher compared to the control. A number of MC and immunoreactive nerve fibers were observed in the skin and of histamine-immunoreactive MC in the thyroid of exposed animals. The differences in stereological data were not statistically significant by the Mann-Whitney test.
  
  
  CONCLUSIONS
  The results indicate certain alterations of cutaneous and thyroid MC in rats exposed to EMF. However, the possible outcome of changes in the MC population under EMF influence on morphophysiological properties of other structures in skin and thyroid requires further investigation.
authors.affiliation: Department of Biology, Faculty of Sciences, Novi Sad, Serbia and Montenegro. vesna.rajkovic@ib.ns.ac.yu
authors.forename: Vesna
authors.initials: V
authors.lastname: Rajkovic
authors.forename: Milica
authors.initials: M
authors.lastname: Matavulj
authors.forename: Olle
authors.initials: O
authors.lastname: Johansson
mesh_terms: D000818:Animals; D004574:Electromagnetic Fields / Q000009:adverse effects*; D007150:Immunohistochemistry; D008297:Male; D008407:Mast Cells / Q000528:radiation effects; D009412:Nerve Fibers / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000166:cytology / Q000528:radiation effects; D013961:Thyroid Gland / Q000166:cytology / Q000528:radiation effects*