[Preliminary study on role of lipid rafts in receptor clustering induced by 50 Hz magnetic fields and its mechanism].
To investigate the relationship among a 50 Hz magnetic field (MF)-induced epidermal growth factor receptor (EGFR) clustering,lipid rafts and acid sphingomyelinase (ASM), and to explore its possible mechanism.



Human amnion FL cells were exposed to 50 Hz, 0.4 mT MF for 15 min. EGF treatment was used as positive control. Nystatin was employed to study lipid rafts since it could disrupt lipid rafts structure.The EGF receptors, ASM and lipid rafts were labeled with polyclonal anti-EGFR antibody, anti-ASM antibody and FITC-Cholera toxin B, respectively. The images were observed by laser confocal scanning microscope.



Both EGF treatment and 50 Hz MF exposure could induce EGFR clustering; however, nystatin pretreatment disrupted this effect. MF exposure turned ASM (labeled with Cy3) from a diffused state in the sham exposure group to a concentrated state on the cell membrane, which co-localized with lipid rafts (labeled with FITC).



The results suggest that the EGFR clustering induced by 50 Hz MF depends on intact lipid rafts on cellular membrane, and the ASM might participate in the process of EGFR clustering.
Wang
Yong
Y
Bioelectromagnetics Laboratory of Zhejiang Province, College of Medicine, Zhejiang University, Hangzhou 310058, China.
Chen
Qing
Q
Lu
De-qiang
DQ
Xu
Zheng-ping
ZP
Jiang
Huai
H
Sun
Wen-jun
WJ
D002462:Cell Membrane / Q000528:radiation effects; D002478:Cells, Cultured; D004574:Electromagnetic Fields; D004815:Epidermal Growth Factor / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism / Q000528:radiation effects*; D006801:Humans; D021962:Membrane Microdomains / Q000528:radiation effects*; D015398:Signal Transduction / Q000502:physiology / Q000528:radiation effects*; D013108:Sphingomyelin Phosphodiesterase / Q000378:metabolism
D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D013108:Sphingomyelin Phosphodiesterase