Kim Ju Hwan, Kim Hyo-Jeong, Yu Da-Hyeon, Kweon Hee-Seok, Huh Yang Hoon, Kim Hak Rim
Department of Pharmacology, College of Medicine, Dankook University, Cheonan, Chungnam, South Korea.
Center for Electron Microscopy Research, Korea Basic Science Institute, Ochang, Chungbuk, South Korea.
PLoS One. 2017 Oct 18;12(10):e0186416. doi: 10.1371/journal.pone.0186416. eCollection 2017.
We studied the effects of radiofrequency electromagnetic fields (RF-EMFs) exposure on neuronal functions of mice. Particularly, we focused on RF-EMF effects on synaptic vesicles (SVs), which store neurotransmitters at axon terminals or synaptic boutons. C57 BL/6 mice were exposed to 835 MHz RF-EMF (4.0 W/kg SAR, for 5 h daily) and alterations in SVs at presynaptic terminals in the cerebral cortex were determined. Ultrastructure of randomly selected cortical neurons was observed using typical electron microscopy and bio-high voltage electron microscopy (Bio-HVEM) methods, which enable the estimation of the numbers and size of SVs. The density of the SVs (number /10 μm2 or 40 μm3) was significantly decreased in the presynaptic boutons of cortical neurons after RF-EMF exposure. Furthermore, qPCR and immunoblotting analyses revealed that the expression of synapsins I/II (Syns I/II) genes and proteins were significantly decreased in the cortical neurons of RF-EMF exposed mice. The present study suggested that alteration of SVs and Syn levels may result in alterations of neurotransmitters in the cerebral cortex following RF-EMF exposure.
我们研究了射频电磁场（RF-EMFs）暴露对小鼠神经元功能的影响。特别地，我们关注RF-EMF对突触小泡（SVs）的影响，突触小泡在轴突终末或突触小体中储存神经递质。将C57 BL/6小鼠暴露于835 MHz的RF-EMF（比吸收率为4.0 W/kg，每天5小时），并确定大脑皮层突触前终末处SVs的变化。使用典型的电子显微镜和生物高压电子显微镜（Bio-HVEM）方法观察随机选择的皮层神经元的超微结构，这些方法能够估计SVs的数量和大小。RF-EMF暴露后，皮层神经元突触前小体中SVs的密度（数量/10μm2或40μm3）显著降低。此外，定量聚合酶链反应（qPCR）和免疫印迹分析表明，暴露于RF-EMF的小鼠皮层神经元中突触结合蛋白I/II（Syns I/II）基因和蛋白的表达显著降低。本研究表明，RF-EMF暴露后，SVs和突触结合蛋白水平的改变可能导致大脑皮层神经递质的改变。
