Magnetic field exposure increases cell proliferation but does not affect melatonin levels in the mammary gland of female Sprague Dawley rats
Authors not listed · 2002
Female Sprague Dawley rats exposed for 2 weeks at 100 microTesla showed increased mammary epithelial cell proliferation but no change in melatonin levels.
Plain English Summary
Female Sprague Dawley rats were MF or sham exposed for 2 weeks at a flux density of 100 microTesla. Proliferation of epithelial cells in the mammary tissue and adjacent skin was examined by in vivo labeling with bromodeoxyuridine (BrdUrd) and in situ labeling of Ki-67 protein by the antibody MIB-5. MF exposure significantly enhanced BrdUrd and Ki-67 labeling in the mammary epithelium, indicating a marked increase in cell proliferation. Melatonin levels in pineal or mammary glands were not affected by MF exposure. Topical application of 12-O-tetradecanoylphorbol-13-acetate increased BrdUrd and Ki-67 labeling in skin epithelial cells, particularly hair follicles, but not in mammary tissue.
Why This Matters
The study was motivated by a previous finding that 50-Hz magnetic fields at 100 microTesla enhanced mammary tumor development in a DMBA model. The researchers hypothesized that magnetic fields might promote carcinogenesis by increasing proliferation of the mammary epithelium, based on the melatonin hypothesis and prior observations of ornithine decarboxylase induction. The objective was to directly assess this proposal by the use of proliferation markers.
Exposure Information
Specific exposure levels were not quantified in this study.
Show BibTeX
@article{magnetic_field_exposure_increases_cell_proliferation_but_does_not_affect_melatonin_levels_in_the_mammary_gland_of_female_sprague_dawley_rats_ce1512,
author = {Unknown},
title = {Magnetic field exposure increases cell proliferation but does not affect melatonin levels in the mammary gland of female Sprague Dawley rats},
year = {2002},
}