毫米波辐射对子鼠学习记忆功能和脑内单胺递质的影响

Effects of millimeter wave irradiation with different frequency at different power density on the posterities of mice

目的确定毫米波导致胚胎损伤阈值及导致子鼠学习记忆功能降低机理，验证毫米波有无频率特异性。方法用３７．４～６０ＧＨｚ、功率密度１～８ｍＷ／ｃｍ２的毫米波，在小鼠怀孕６～１５ｄ时进行２ｈ／ｄ辐射，用电迷宫对子鼠进行学习记忆功能测试，用高效液相色谱电化学检测（ＨＰＬＣＥＣＤ）对子鼠脑单胺递质进行测定。结果３７．４、４２．２ＧＨｚ和５３、６０ＧＨｚ毫米波导致子鼠学习记忆功能降低、脑中多巴胺（ＤＡ）含量下降的最小功率密度分别为５和３ｍＷ／ｃｍ２，随功率密度增加，辐射导致胎仔损伤程度加重。毫米波未使孕鼠辐射区皮肤温度明显升高。结论３７．４、４２．２ＧＨｚ和５３、６０ＧＨｚ毫米波导致胚胎损伤阈值分别为３～５ｍＷ／ｃｍ２和１～３ｍＷ／ｃｍ２，其导致子鼠学习记忆功能降低与使子鼠脑中ＤＡ含量下降密切相关，此效应由毫米波非热效应所致。

Objective To determine the threshold of fetuses injury induced by millimeter wave irradiation and to clarify the mechanism of lowering learning capacity and memory of the adult offspring,and to verify whether millimeter wave has frequency specific effect.Methods Two month old BALB/c mice were separately irradiated by millimeter wave with frequencies of 37.4 ～60 GHz at power densities of 1～8 mW/cm 2 for 2 h daily from 6th to 15th day of gestation.The test of learning capacity and memory of the adult offspring was employed on Y type electric maze.The contents of monoamine transmitter in the brain of the fetuses at term,adult offspring were measured by using HPLC ECD.Results Millemeter wave irradiation at frequency of 37.4 , 42.2 GHz and 53,60 GHz,with minimum power density of 5 and 3 mW/cm 2,lowered learning and memory ability of adult offspring and reduced the content of dopamine in their brains.As the power density increased,the injury of fetuses became more severe.Millimeter wave irradiation did not significantly increase the regional skin temperature of pregnant mice.Conclusion The thresholds of fetus injury induced by millimeter wave irradiation at frequency of 37.4 , 42.2 GHz and 53,60 GHz are 3～5 mW/cm 2 and 1～3 mW/cm 2 separately.The mechanism that millimeter wave irradiation lowered learning ability and memory of the adult offspring is closely related to decrease of dopamine in the brain.There is an athermal effect of millimeter wave.There is no frequency specific effect.