Jauchem J R, Frei M R
Biological Effects Branch, Radiofrequency Radiation Division, U.S. Air Force Armstrong Laboratory, Brooks Air Force Base, TX, USA.
Aviat Space Environ Med. 1995 Oct;66(10):992-7.
Exposure sources capable of generating high-peak-power microwave pulses, with relatively short pulse widths, have recently been developed. Studies of the effect of these sources on the cardiovascular systems of animals have not been reported previously.
We exposed 14 unanesthetized male Sprague-Dawley rats to 10 high-peak-power microwave pulses generated by a transformer-energized megawatt pulsed output (TEMPO) microwave source, at frequencies ranging from 1.2-1.8 GHz. Peak power densities were as high as 51.6 kW/cm2. At 14 d prior to irradiation, the animals were implanted with chronic aortic cannulae. With appropriate shielding of the transducer, blood pressure recordings were obtained during microwave pulsing.
In a preliminary series of exposures at 1.7-1.8 GHz (peak power density 3.3-6.5 kW/cm2), an immediate but transient increase in mean arterial blood pressure (significant) and decrease in heart rate (non-significant) were observed. A loud noise was associated with each pulse produced by the TEMPO; this factor was subsequently attenuated. In a second series of exposures at 1.2-1.4 GHz (peak power density 14.6-51.6 kW/cm2), there were no significant changes in mean arterial blood pressure or heart rate during microwave exposure.
The earlier significant increase in blood pressure that occurred during microwave exposure appeared to be related to the sharp noise produced by the TEMPO source. After appropriate sound attenuation, there were no significant effects of exposure to the microwave pulses.
最近已开发出能够产生具有相对短脉冲宽度的高功率微波脉冲的辐射源。此前尚未有关于这些辐射源对动物心血管系统影响的研究报道。
我们将14只未麻醉的雄性Sprague-Dawley大鼠暴露于由变压器激励的兆瓦脉冲输出（TEMPO）微波源产生的10个高功率微波脉冲下，频率范围为1.2 - 1.8 GHz。峰值功率密度高达51.6 kW/cm²。在照射前14天，给动物植入慢性主动脉插管。在对换能器进行适当屏蔽的情况下，在微波脉冲期间记录血压。
在1.7 - 1.8 GHz（峰值功率密度3.3 - 6.5 kW/cm²）的初步系列暴露中，观察到平均动脉血压立即但短暂升高（显著），心率下降（不显著）。每个由TEMPO产生的脉冲都伴随着一声巨响；该因素随后得到了减弱。在1.2 - 1.4 GHz（峰值功率密度14.6 - 51.6 kW/cm²）的第二系列暴露中，微波暴露期间平均动脉血压或心率没有显著变化。
微波暴露期间早期出现的血压显著升高似乎与TEMPO源产生的尖锐噪声有关。经过适当的声音衰减后，微波脉冲暴露没有显著影响。
