不同强度工频磁场对神经元电压门控离子通道的影响

发布时间：2018-09-11 06:09

【摘要】：随着科学技术的发展,各种家用电器及通信设备在人们的生活中日益普及,磁场在环境中的分布越来越广泛。磁场的生物效应备受人们的关注,但是磁场的作用机制尚无定论,大量的实验数据积累以及理论分析是非常有必要的。本研究选用1 mT、5 mT和10 mT的工频磁场照射急性分离的小鼠皮层神经元(15 min),应用全细胞膜片钳技术记录电压门控钠、钾离子通道电流,从细胞电生理学的角度研究工频磁场对离子通道特性的影响,包括工频磁场对电压门控钠、钾通道电流的电压、磁场强度的依赖性以及工频磁场对通道稳态激活和失活动力学特征的影响。本论文的研究结果包括:(1)1 mT、5 mT和10 mT工频磁场影响小鼠皮层神经元钠通道电流,1 mT和10 mT工频磁场暴露增大钠通道电流而5 mT工频磁场抑制钠通道电流。另外,不同强度的工频磁场影响钠通道的激活和失活特性,但激活和失活参数的改变程度不同。(2)不同强度工频磁场对瞬时外向钾通道电流均有显著的抑制作用,磁场强度不同抑制率也不同;另外,与对照组相比,不同强度的工频磁场对瞬时外向钾通道的激活和失活特性均有一定的影响。(3)不同强度的工频磁场抑制延迟整流钾通道电流,但随着去极化电压的增加,不同强度工频磁场对通道电流密度的抑制率曲线的走势不同;另外,1 mT和5 mT工频磁场改变了延迟整流钾通道的激活特性,而10 mT工频磁场不改变通道的激活特性。本课题应用全细胞膜片钳技术,从电生理学的角度研究了不同强度工频磁场的生物效应。研究结果不仅为磁场生物效应的研究积累了数据,而且也为揭示磁场的作用机制奠定了数据基础。
[Abstract]:With the development of science and technology, all kinds of household appliances and communication equipments are becoming more and more popular in our daily life, and the magnetic field is more and more widely distributed in the environment. The biological effect of magnetic field has attracted much attention, but the mechanism of magnetic field action has not been decided. A large amount of experimental data accumulation and theoretical analysis are very necessary. In this study, 1 mT,5 mT and 10 mT power frequency magnetic fields were used to irradiate acutely isolated mouse cortical neurons (15 min), whole-cell patch-clamp technique was used to record voltage-gated sodium and potassium channel currents. The influence of power frequency magnetic field on the characteristics of ion channel was studied from the point of view of cell electrophysiology, including the voltage of power frequency magnetic field on voltage-gated sodium and potassium channel current. The dependence of magnetic field intensity and the influence of power frequency magnetic field on the dynamic characteristics of steady state activation and inactivation of channels. The results are as follows: (1) 1 mT,5 mT and 10 mT power frequency magnetic fields affect the sodium channel currents of cortical neurons in mice (1 mT and 10 mT), and 5 mT power frequency magnetic field inhibits sodium channel currents. In addition, different intensity of power frequency magnetic field affects the activation and inactivation of sodium channel, but the change of activation and inactivation parameters is different. (2) different intensity of power frequency magnetic field has significant inhibitory effect on transient outward potassium channel current. In addition, compared with the control group, different intensity of power frequency magnetic field has certain influence on the activation and inactivation of transient outward potassium channel. (3) different intensity of power frequency magnetic field inhibits the current of delayed rectifier potassium channel. However, with the increase of depolarization voltage, the inhibition rate curves of current density of different intensity power frequency magnetic fields are different, in addition, 1 mT and 5 mT power frequency magnetic fields change the activation characteristics of delayed rectifier potassium channels. However, 10 mT power frequency magnetic field does not change the activation characteristics of the channel. In this paper, the biological effects of different intensity power frequency magnetic fields were studied by using whole-cell patch clamp technique from the electrophysiological point of view. The results not only accumulate the data for the study of the biological effect of magnetic field, but also lay the data foundation for revealing the mechanism of the magnetic field.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.0

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