不同功率密度的微波辐射对小鼠学习记忆功能的影响
Effects of different power densities of microwave radiation on learning and memory ability of mice
-
摘要:
目的 观察频率为2 450 MHz的不同功率密度微波辐射对小鼠学习记忆功能的影响，并探究其影响机制。
方法 将40只5周龄昆明种小鼠作为观察对象，雌雄各半，随机分为对照组和3个辐射组。辐射组连续暴露于频率为2 450 MHz的微波辐射28 d，1.5 h/d，功率密度分别为2.5、5.0、10.0 mW/cm2。通过Y迷宫实验和避暗实验观察各组小鼠学习记忆能力改变。检测小鼠脑组织中超氧化物歧化酶（SOD）活性、S100B蛋白、一氧化氮（NO）、天冬氨酸（Asp）、γ-氨基丁酸（GABA）及谷氨酸（Glu）含量。
结果 各辐射组小鼠Y迷宫错误逃逸次数明显增高，脑组织中SOD活性及Glu含量降低（P < 0.01或P < 0.05）；10.0mW/cm2辐射组小鼠避暗实验错误次数增加（P < 0.01）；5.0、10.0 mW/cm2辐射组小鼠避暗实验潜伏期减少，小鼠脑组织中S100B蛋白浓度升高，NO及GABA含量增高，Asp含量降低，与对照组相比，具有统计学差异（P < 0.01或P < 0.05）；随着微波辐射暴露功率密度的增加，损伤逐渐加重。
结论 微波辐射可导致小鼠学习记忆功能减弱，其机制可能为微波辐射造成脑组织氧化损伤，使脑组织中S100B蛋白含量增高，导致NO浓度增加，进而造成Glu等氨基酸类神经递质代谢紊乱，从而损害小鼠学习记忆能力减弱。
Abstract:Objective To observe the effects of microwave radiation at 2 450 MHz with different power densities on learning and memory ability of mice.
Methods Forty 5-week-old Kunming mice were (1:1 sex ratio) randomly divided into four groups with ten mice each:control group, 2.5mW/cm2 radiation group, 5.0 mW/cm2 radiation group, and 10.0 mW/cm2 radiation group. Three radiation groups were exposed to microwave radiation (2 450 MHz) for 28 days, 1.5 h/d. The changes of learning and memory ability were evaluated with Y maze test and step-through test. The activity of superoxide dismutase (SOD) and the levels of S100B protein, nitric oxide (NO), aspartic acid (Asp), gamma amino acid (GABA), and glutamate (Glu) were determined, respectively.
Results Compared with the control group, the incorrect run counts of Y-maze test in the three radiation groups were higher, the activity of SOD and the level of Glu were lower (P < 0.01 or P < 0.05). In the step-through test, the incorrect counts of the 10.0 mW/cm2 radiation group was higher (P < 0.01); the latencies of both the 5.0 mW/cm2 and the 10.0 mW/cm2 radiation groups were obviously lower than that of the control group, the levels of S100B protein were higher, the levels of NO and GABA were increased, and the levels of Asp were decreased (P < 0.01 or P < 0.05). With the increase of power density of microwave irradiation, the damage gradually aggravated.
Conclusion Microwave radiation can affect learning and memory ability of mice. Microwave radiation may cause oxidative damage, increase the levels of S100B protein and NO, and induce metabolic disturbance of amino acid neurotransmitters, which results in impaired learning and memory ability of mice.
下载:
