Some central cholinergic effects have been reported in animals after acute exposure to radiofrequency electromagnetic field at low intensity. We studied acetylcholine (ACh) release in the brain of freely moving rats exposed for 1 h during the day to a 2.45 GHz continuous wave radiofrequency field (RF) (2 or 4 mW/cm(2)) or exposed for 1 or 14 h during the night to a 800 MHz field modulated at 32 Hz (AM 200 mW/cm(2)). Measurements were performed by microdialysis using a membrane implanted through the upper CA1 region of the hippocampus. After irradiation with the 2.45 GHz RF, rats exposed at 2 mW/cm(2) did not show a significant modification of Ach release, whereas those exposed at 4 mW/cm(2) showed a significant 40% decrease in mean ACh release from hippocampus. This decrease was maximal at 5 h post exposure. Exposure to the 800 MHz RF for 1 h did not cause any significant effect, but exposure for 14 hrs induced a significant 43% decrease in ACh release during the period 11 p.m.-4 a.m. compared to control rats. In the control group we observed an increase of ACh release at the beginning of the night, which was linked to the waking period of rats. This normal increase was disturbed in rats exposed overnight to the 800 MHz RF. This work indicates that neurochemical modification of the hippocampal cholinergic system can be observed during and after an exposure to low intensity RF.

中文翻译：

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暴露于低水平射频场对自由活动大鼠海马乙酰胆碱释放的影响。

据报道，动物在低强度急性暴露于射频电磁场后会产生一些中枢胆碱能作用。我们研究了自由活动大鼠白天暴露于2.45 GHz连续波射频场（RF）（2或4 mW / cm（2））或暴露1或14 h的自由运动大鼠大脑中乙酰胆碱（ACh）的释放在夜间调制为32 Hz（AM 200 mW / cm（2））的800 MHz场。使用通过海马上部CA1区植入的膜通过微透析进行测量。用2.45 GHz RF辐射后，暴露于2 mW / cm（2）的大鼠未显示Ach释放的显着改变，而暴露于4 mW / cm（2）的大鼠显示Ach释放的平均Ach释放显着降低40％海马。暴露后5小时该下降最大。与对照大鼠相比，暴露于800 MHz RF 1小时没有引起任何显着影响，但暴露14小时导致Apm释放在上午11点至凌晨4点期间显着降低了43％。在对照组中，我们观察到在夜晚开始时ACh释放增加，这与大鼠的清醒期有关。过夜暴露于800 MHz RF的大鼠干扰了这种正常的增加。这项工作表明，在暴露于低强度射频期间和之后，可以观察到海马胆碱能系统的神经化学修饰。这与大鼠的清醒时期有关。过夜暴露于800 MHz RF的大鼠干扰了这种正常的增加。这项工作表明，在暴露于低强度射频期间和之后，可以观察到海马胆碱能系统的神经化学修饰。这与大鼠的清醒时期有关。过夜暴露于800 MHz RF的大鼠干扰了这种正常的增加。这项工作表明，在暴露于低强度射频期间和之后，可以观察到海马胆碱能系统的神经化学修饰。