School of Electronics and Information Engineering, Tianjin Polytechnic University, Tianjin, 300387, China.
School of Electronics and Information Engineering, Tianjin Polytechnic University, Tianjin, 300387, China.
Biochem Biophys Res Commun. 2019 Sep 24;517(3):513-519. doi: 10.1016/j.bbrc.2019.07.085. Epub 2019 Jul 31.
Exposure to environmental electromagnetic fields, especially to the extremely low-frequency (ELF < 300 Hz) electromagnetic fields (EMFs) might produce modulation effects on neuronal activity. Long-term changes in synaptic plasticity such as long-term potentiation (LTP) involved in learning and memory may have contributions to a number of neurological diseases. However, the modulation effects of ELF-EMFs on LTP are not yet fully understood. In our present study, we aimed to evaluate the effects of exposure to ELF-EMFs on LTP in hippocampal CA1 region in rats. Hippocampal slices were exposed to magnetic fields generated by sXcELF system with different frequencies (15, 50, and 100 Hz [Hz]), intensities (0.5, 1, and 2 mT [mT]), and duration (10 s [s], 20 s, 40 s, 60 s, and 5 min), then the baseline signal recordings for 20 min and the evoked field excitatory postsynaptic potentials (fEPSPs) were recorded. We found that the LTP amplitudes decreased after magnetic field exposure, and the LTP amplitudes decreased in proportion to exposure doses and durations, suggesting ELF-EMFs may have dose and duration-dependent inhibition effects. Among multiple exposure duration and doses combinations, upon 5 min magnetic field exposure, 15 Hz/2 mT maximally inhibited LTP. Under 15 Hz/2 mT ELF-EMFs, LTP amplitude decreases in proportion to the length of exposure durations within 5 min time frame. Our findings illustrated the potential effects of ELF-EMFs on synaptic plasticity and will lead to better understanding of the influence on learning and memory.
暴露于环境电磁场中，尤其是极低频（ELF<300Hz）电磁场（EMFs）可能对神经元活动产生调制作用。参与学习和记忆的突触可塑性的长期变化，如长时程增强（LTP），可能对许多神经疾病有贡献。然而，ELF-EMFs 对 LTP 的调制作用尚不完全清楚。在本研究中，我们旨在评估暴露于 ELF-EMFs 对大鼠海马 CA1 区 LTP 的影响。海马切片暴露于 sXcELF 系统产生的磁场中，频率分别为 15、50 和 100Hz（Hz），强度分别为 0.5、1 和 2mT（mT），持续时间分别为 10s、20s、40s、60s 和 5min，然后记录 20min 的基线信号和诱发的场兴奋性突触后电位（fEPSPs）。我们发现磁场暴露后 LTP 幅度减小，且 LTP 幅度与暴露剂量和时间呈比例下降，表明 ELF-EMFs 可能具有剂量和时间依赖性抑制作用。在多种暴露时间和剂量组合中，5min 磁场暴露时，15Hz/2mT 最大程度地抑制 LTP。在 15Hz/2mT 的 ELF-EMFs 下，LTP 幅度随暴露时间的延长而呈比例下降，在 5min 时间范围内。我们的研究结果说明了 ELF-EMFs 对突触可塑性的潜在影响，并将导致对学习和记忆影响的更好理解。
