正弦波磁场发生器的研制及其对钾通道电流的影响

目的:研制一种低频的正弦波磁场发生装置,使产生的磁场频率和场强等参数均可调节,并且能在生物学实验研究中方便的使用。方法:首先设计一个直流稳压电源为电路各部分提供直流电压,然后用单片机控制正弦信号生成,分离元件组成功放电路,功放实际可提供的电流为0mA～136mA。根据实验的需要自行设计线圈,线圈的几何尺寸和匝数不同,所得到的场强值也不同。结果:该仪器产生的磁场输出频率在0kHz～25kHz,强度在0mT～10mT范围内连续可调,电源功率在30W内时可连续长时间工作。该磁场发生装置运行稳定,使用方便,所得到的场强值与理论推导出来的基本相符,能应用于生物效应的研究。结论:用该仪器生成的不同频率、不同场强的磁场对大鼠的海马神经元进行照射,发现正弦波磁场对海马神经元钾离子通道的电流特性有一定的影响,可能存在频率和场强的"窗口"效应。

Development of Sine Wave Magnetic Field Generator and Effects on Potassium Channel Current

Purpose: A kind of sine wave magnetic field generator with the extremely low frequency (ELF) is developed, the frequency and intensity of the magnetic field can be adjusted, and has been easily used in Bio-experimental study. Methods: At first ,we design a DC power supply which provide DC voltage to other chips,then the signal generated by single chip ma-chine system and the power amplifier combined by discrete components, it provides current 0 mA～136 mA.The current coil is designed by experiment's required,the size or turns is changed, the magnetic field intensity is changed too. Results: The fre-quency of the device output is 0 kHz-25 kHz with the intensity in the range of 0 mT～10 mT within which the continuous lin-earity is adjustable. Power sources are less than 30 W ,which can work for long.This device performs reliably and the measured values in accord with the theoretical values and has been used in the experiment of magnetic biological effect. Conclusions: The experiment results indicate that there exist the effects of ELF sine wave magnetic field upon potassium current of neurons, and that such bioeffects vary with the intensity and frequency of the field.Also,there may exist "window" effect areas.