title: Can intermediate-frequency magnetic fields affect memory function-related gene expressions in hippocampus of C57BL/6J mice?
abstract: Recently, a cooking appliance based on the principle of electromagnetic induction has come to be used domestically on a widespread basis; this induction heating cooking hob mainly generates intermediate-frequency magnetic fields (IF-MF). However, whether electromagnetic fields originating from household appliances represent a health risk remains uncertain. We investigated the effect of IF-MF on the expressions of memory function-related genes and related transduction molecules in the mouse hippocampus. Male and female C57BL/6J mice were allotted to a control (sham-exposed), an exposure, or a recovery (one week after exposure) group and were exposed to IF-MF (21 kHz, 3.8 mT) one hour per day for 2 weeks. Twenty-four hour after final exposure, the expression levels of memory function-related genes and the mRNA levels for signal transduction pathway molecules in the hippocampi were examined using real-time RT-PCR. The relative mRNA expression levels of the N-methyl-D aspartate (NMDA) receptor subunits NR1, NR2A, and NR2B as well as transcription factors (calcium/calmodulin-dependent protein kinase (CaMK) -IV, cyclic AMP responsive element binding protein (CREB) -1) and neurotrophins (nerve growth factor (NGF), and brain-derived neurotrophic factors (BDNF)) were not significantly altered in the IF-MF-exposed mice. We also examined the morphology of the hippocampus using a histological analysis, but no changes in the IF-MF-exposed mice were seen. This is the first in vivo study to show that IF-MF exposure did not affect the expression levels of memory function-related genes in the hippocampus of C57BL/6J mice. The present findings suggest that IF-MF exposure may not affect cognitive function in the present animal model.
authors.affiliation: Center for Environmental Health Sciences, National Institute for Environmental Studies, Ibaraki, Japan.
authors.forename: Tin-Tin
authors.initials: TT
authors.lastname: Win-Shwe
authors.forename: Shin
authors.initials: S
authors.lastname: Ohtani
authors.forename: Akira
authors.initials: A
authors.lastname: Ushiyama
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Fujimaki
authors.forename: Naoki
authors.initials: N
authors.lastname: Kunugita
mesh_terms: D000818:Animals; D005260:Female; D015870:Gene Expression; D006624:Hippocampus / Q000502:physiology*; D060526:Magnetic Fields / Q000009:adverse effects*; D008297:Male; D008568:Memory; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D009414:Nerve Growth Factors / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics
chemical_list: D009414:Nerve Growth Factors; D012333:RNA, Messenger; D016194:Receptors, N-Methyl-D-Aspartate; D014157:Transcription Factors