低频脉冲磁场对大鼠皮质神经元损伤效应

目的探讨低频脉冲磁场对大鼠皮质神经元的损伤效应及其可能机制。方法体外研究中,分离培养胎鼠大脑皮质神经元,对实验组神经元施加低频脉冲磁场辐射（频率15Hz,平均场强0.1mT）,检测神经元的形态学变化、相对存活率和胞浆内游离Ca^2＋浓度的变化。体内研究中,对实验组大鼠施加与体外研究相同频率和强度的脉冲磁场辐射,检测脑组织形态学的变化。结果实验组神经元胞质内可见髓样体及线粒体聚集现象;实验组神经元相对存活率为81.17%,明显低于对照组（P〈0.01）;胞浆内游离Ca^2＋浓度比对照组升高17.29%（P〈0.01）。实验组大鼠的皮质神经元出现异常改变。结论低频脉冲磁场辐射可导致培养的皮质神经元代谢异常、胞浆内游离Ca^2＋浓度升高及成年大鼠皮质神经元凋亡。

Damaging effects of low-frequency pulsed magnetic field on cortical neurons

Objective To investigate the damaging effects and the possible mechanism of low-frequency pulsed magnetic field using a combination of in vitro and in vivo approaches.Methods In vitro,primary cortical neurons were prepared from embryonic Wistar rats.The neurons of experimental group were exposed to Low-frequency Pulsed Magnetic Field(frequency:15 Hz,average magnetic field intensity:0.1 mT) for 2 days,3 times/d,30 minutes/time.The morphology,the relative viability and the intracellular calcium level of neurons after exposure were determined.In vivo,the rats in experimental group were exposed to the same low-frequency pulsed magnetic field for 30 days,45 min/d.The morphological changes were observed.Results In vitro,myeloid body and mitochondrial aggregation inside the cyton were observed in the experimental group,the relative viability of neurons in experimental group was 81.17%,which decreased significantly than that of the control goup(P<0.01),the intracellular calcium level of neurons in experimental group increased significantly(P<0.01).In vivo,compared with the control group,abnormal changes of neurons were observed in experimental group.Conclusion The irradiating with low-frequency pulsed magnetic field resulted in metabolic abnormality,elevated intracellular free calcium level of neurons in vitro and apoptosis of neurons in vivo.