Medical/biological Study (experimental study)
Gene expression in the mammary gland tissue of female Fischer 344 and Lewis rats after magnetic field exposure (50 Hz, 100 muT) for 2 weeks. med./biol. By: Fedrowitz M, Loscher W
Published in: Int J Radiat Biol 2012; 88 (5): 425 - 429 ( PubMed Entry , Journal web site )
Aim of study (according to author)
To elucidate magnetic field effect-associated candidate genes, gene expression in magnetic field-susceptible Fischer 344 rats and magnetic field-insensitive Lewis rats was compared (to explain the different strain sensitivity to magnetic field exposure as shown in a previous studies: Fedrowitz and Löscher 2008 and Fedrowitz and Löscher 2005).
Five rats per group at an age of 52 days were exposed and five rats per group were sham exposed (in total n=20). A total of four arrays were performed with the pooled RNA of sham exposed or exposed Fischer 344 rats and Lewis rats.
General category: magnetic field, low frequency field, 50/60 Hz (AC)
FIELD View further expo parameters
animal (species/strain): rat/Fischer 344 and Lewis
whole body exposure
Methodsinvestigated material: DNA/RNA (in vitro)
organ system(s): mammary gland
time of investigation: during and after exposure
Main outcome of study (according to author)
The analysis of gene expression in the mammary gland tissue revealed
that altogether only 23 transcripts out of 31,100 probe sets were altered after
magnetic field exposure.
In the breast tissue of Lewis rats, nine genes were upregulated, whereas eight upregulations and six downregulations
of gene expressions were apparent in magnetic field exposed Fischer 344
A remarkably decreased alpha-amylase gene expression, downregulations in carbonic anhydrase 6 and lactoperoxidase (both relevant for pH regulation), and an upregulated gene expression of cystatin E/M (a tumor suppressor) were found in exposed Fischer 344 rats, but not in Lewis rats.
In conclusion, the magnetic field exposed breast tissue of Fischer 344 rats showed alterations in gene expression, which were absent in Lewis rats and may therefore be involved in the magnetic field-susceptibility of Fischer 344 rats. Alpha-amylase might serve as a promising target to study magnetic field effects.
(Study character: medical/biological study, experimental study, full/main study, blind study)
Study funded by
- Deutsche Forschungsgemeinschaft (DFG; German Research Foundation)
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Glossary: 50/60 Hz, AC, amylase, animal, Arrays, biological, biosynthesis, blind study, candidate genes, carbonic anhydrase, DNA, downregulations, effective value, endpoint, exposed, exposure, Fischer 344, full/main study, gene expression, genes, genome, in vitro, low frequency field, magnetic field, magnetic flux density, mammary gland, microarray, molecular, pH, pooled, probe, rats, RNA, sensitivity, sham exposed, species, strain, tissue, transcripts, tumor suppressor, upregulated, whole body exposure
Exposure: magnetic field, low frequency field, 50/60 Hz (AC)
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