STUDY ON EFFECTS OF EXTRA LOW FREQUENCY ELECTROMAGNETIC FIELD ON GENERATOR OF BIORHYTHM

研究了超低频电磁场对生物节律发生器视交叉上核电活动的影响。首先，我开发了一个保持器，用它可以在几天内测量昼夜节律。进行了50Hz磁场对SCN活性影响的实验研究。将玻璃涂层双极金属微电极立体定位地插入麻醉大鼠的SCN中，以测量SCN的细胞外活性。术后2周，将大鼠置于屏蔽室内，头部水平固定，保持器置于线圈系统中心，线圈系统可产生均匀磁场。实验大鼠分别暴露于垂直轴（z轴）、平行于头部纵轴（x轴）和垂直于x轴的水平面（y轴）上的50 Hz正弦磁场。结果表明，磁场暴露实验中，SCN活动节律在沿着x轴和y轴方向上均出现相位延迟。研究了极低频磁场对SCN自由活动的影响。手术后将大鼠置于uva暗室中饲养两周以上。暴露于ELF磁场的第二天，观察到SCN电活动的昼夜节律的扭曲。

How extra low frequency (ELF) electromagnetic field affects the electrical activity of suparachiasmatic nucleus (SCN) which is the generator of the biorhythrn was investigated. First, I developed a holder with which circadian rhythm can be measured over days. I carried out the experiments about effects of 50 Hz magnetic field to the SCN activity. A glass-coated bipolar metal microelectrode was inserted stereotaxically into the SCN of an anesthetized rat in order to measure the extracellular activity of SCN. Two weeks after the surgical operation, the rat was put into the shielded room and its head was fixed horizontally with the holder at the center of the coil system which can produce uniform magnetic field. The experimental rats were exposed with 50 Hz sinusoidal magnetic field along the vertical axis (z-axis), parallel to the longitudinal axis of the head (x-axis) or perpendicular to x-axis in horizontal plane (y-axis) respectively. The result shows that the phase delay of rhythm of SCN activity was observed in the experiments of magnetic field exposure along x-axis and y-axis. The ettect ot ELF magnetic field to the free-running SCN activity was also investigated. The rat was bred uva dark room for more than two weeks after the surgical operation. The distortion of the circadian rhythm of SCN electrical activity was observed on the next day of the exposure of ELF magnetic field.