title: Exposure to 2.45 GHz electromagnetic fields elicits an HSP-related stress response in rat hippocampus.
abstract: The issue of possible neurobiological effects of the electromagnetic field (EMF) exposure is highly controversial. To determine whether electromagnetic field exposure could act as an environmental stimulus capable of producing stress responses, we employed the hippocampus, a sensitive target of electromagnetic radiation, to assess the changes in its stress-related gene and protein expression after EMF exposure. Adult male Sprague-Dawley rats with body restrained were exposed to a 2.45 GHz EMF at a specific absorption rate (SAR) of 6 W/kg or sham conditions. cDNA microarray was performed to examine the changes of gene expression involved in the biological effects of electromagnetic radiation. Of 2048 candidate genes, 23 upregulated and 18 downregulated genes were identified. Of these differential expression genes, two heat shock proteins (HSP), HSP27 and HSP70, are notable because expression levels of both proteins are increased in the rat hippocampus. Result from immunocytochemistry revealed that EMF caused intensive staining for HSP27 and HSP70 in the hippocampus, especially in the pyramidal neurons of cornu ammonis 3 (CA3) and granular cells of dentate gyrus (DG). The gene and protein expression profiles of HSP27 and HSP70 were further confirmed by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Our data provide direct evidence that exposure to electromagnetic fields elicits a stress response in the rat hippocampus.
authors.affiliation: Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Third Military Medical University, Chongqing, PR China.
authors.forename: Xue-Sen
authors.initials: XS
authors.lastname: Yang
authors.forename: Gen-Lin
authors.initials: GL
authors.lastname: He
authors.forename: Yu-Tong
authors.initials: YT
authors.lastname: Hao
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiao
authors.forename: Chun-Hai
authors.initials: CH
authors.lastname: Chen
authors.forename: Guang-Bin
authors.initials: GB
authors.lastname: Zhang
authors.forename: Zheng-Ping
authors.initials: ZP
authors.lastname: Yu
mesh_terms: D000818:Animals; D015153:Blotting, Western; D004574:Electromagnetic Fields; D015870:Gene Expression / Q000528:radiation effects*; D020869:Gene Expression Profiling; D055551:HSP27 Heat-Shock Proteins / Q000096:biosynthesis*; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D006624:Hippocampus / Q000378:metabolism / Q000528:radiation effects*; D007150:Immunohistochemistry; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D055551:HSP27 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins