低功率2 450 MHz射频磁场对神经元延迟整流钾通道的抑制作用

由于电子设备的广泛使用，人类已经越来越多地暴露在射频磁场的辐射下，但射频磁场的辐射效应却一直不明确．采用全细胞膜片钳技术，记录2 450 MHz射频磁场辐射对小鼠脑皮层神经元延迟整流钾电流IK的影响．利用Ansoft HFSS软件对6 dB全向天线建模仿真，验证距天线2~3 cm处磁场分布均匀，使用Agilent E5070B网络分析仪经该天线发射出2 450 MHz输出功率为39.81 mW电磁场，对细胞进行刺激．实验发现，2 450 MHz低功率射频磁场暴露5、10和15 min对IK均有明显的抑制作用；显著影响IK激活特性，对照组与磁场暴露组半数激活电压分别为（－1.13±2.32）mV和（19.52±1.03）mV(n=10, P <0.05)；斜率因子分别为（23.21±3.29）mV和（13.95±1.27）mV(n=10, P <0.05)．结果表明，低功率射频磁场通过减小延迟整流钾通道电流，影响神经元的生理功能，为进一步研究电磁辐射所引发的生物学效应提供了一种新的方法．

Inhibitory Effects of Neuron Delayed Rectifier Potassium Channel under Low Power 2450 MHz RF Magnetic Field

With the wide applications of electronic devices,people are increasingly exposed on radio frequency(RF) magnetic field.However,the effects of RF magnetic field on people’s health remained unclear.Delayed rectifier potassium current(IK) was studied in isolated rat neurons which were exposed to 2450 MHz radio frequency(RF) magnetic field via whole cell patch clamp technique.Ansoft HFSS was used to simulate 6 db gain omni directional antenna magnetic field distribution.The result showed that magnetic field density uniform distribution where 2~3 cm far from the antenna.The 2 450 MHz RF magnetic field was sent out by a 6 dB gain omni directional antenna attached on an Agilent E5070B net analyzer and the transmitting power was 39.81 mw.Compared to the control group,a significant inhibition on the IK after exposure to low power 2 450 MHz RF magnetic field for 5,10 and 15 min,and RF magnetic field markedly affect the activation process of IK,the half-activation voltage changed from(-1.13 ± 2.32)mV to(19.52 ± 1.03)mV(n=10,P <0.05) and the slope factor changed from(23.21 ± 3.29)mV to(13.95 ± 1.27)mV(n=10,P <0.05).The result shows that the 2 450 MHz RF magnetic field can reduce the delayed rectifier potassium currents,and further influenced the physiological functions of neurons.