Li Xing-wen, Lu De-qiang, Jiang Huai, Sun Wen-jun
Bioelectromeganetics Key Laboratory of Zhejiang Province, School of Medicine, Zhejiang University, Hangzhou 310058, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2009 Sep;27(9):516-9.
To investigate the relationship among a 50-Hz MF-induced epidermal growth factor receptor (EGFR) clustering, acid sphingomyelinase (A-SMase) and ceramide (CER), and to explore the possible mechanism of receptor clustering.
Human amnion (FL) cells were exposed to a 50-Hz sinusoidal magnetic field at 0.4 mT for 15 min with or without imipramine, a specific inhibitor of A-SMase and ceramide pretreatment. EGF treatment served as the positive control and DMSO treatment served as the solvent control. The EGFR was labeled with polyclonal anti-EGFR antibody and the clustering of EGFR was analyzed using immunofluorescence and confocal microscopy. The percentage of cells with EGFR clustering was counted and compared.
Both EGF treatment and 50-Hz MF exposure could induce EGFR clustering. However, the effect could be eliminated by imipramine pretreatment for 4 hours. When FL cells were incubated with ceramide following the imipramine pretreatment for 30 min, EGFR clustering induced by 50-Hz MF exposure could be recovered.
EGFR clustering induced by 50-Hz MF depends on A-SMase activity, and ceramide, as the hydrolyzate from A-SMase might participate in the process of EGFR clustering.
研究50Hz中频磁场（MF）诱导的表皮生长因子受体（EGFR）聚集、酸性鞘磷脂酶（A-SMase）和神经酰胺（CER）之间的关系，并探讨受体聚集的可能机制。
将人羊膜（FL）细胞暴露于0.4mT的50Hz正弦磁场中15分钟，同时使用或不使用丙咪嗪（一种A-SMase的特异性抑制剂）进行预处理以及神经酰胺预处理。以表皮生长因子（EGF）处理作为阳性对照，以二甲基亚砜（DMSO）处理作为溶剂对照。用多克隆抗EGFR抗体标记EGFR，并使用免疫荧光和共聚焦显微镜分析EGFR的聚集情况。计算并比较具有EGFR聚集的细胞百分比。
EGF处理和50Hz MF暴露均可诱导EGFR聚集。然而，丙咪嗪预处理4小时可消除该效应。在丙咪嗪预处理30分钟后，将FL细胞与神经酰胺孵育，50Hz MF暴露诱导的EGFR聚集可恢复。
50Hz MF诱导的EGFR聚集依赖于A-SMase活性，并且神经酰胺作为A-SMase的水解产物可能参与EGFR聚集过程。
