Fourth Military Medical University, Department of Radiation Medicine, Xi'an, PR China.
Int J Radiat Biol. 2011 Dec;87(12):1147-54. doi: 10.3109/09553002.2011.584937. Epub 2011 Sep 19.
To investigate the effects of electromagnetic pulses (EMP) on associative learning in mice and test a preliminary mechanism for these effects.
A tapered parallel plate gigahertz transverse electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose male BALB/c mice to EMP (peak-intensity 400 kV/m, rise-time 10 ns, pulse-width 350 ns, 0.5 Hz and total 200 pulses). Concurrent sham-exposed mice were used as a control. Associative learning, oxidative stress in the brain, serum chemistry and the protective action of tocopherol monoglucoside (TMG) in mice were measured, respectively.
(1) Twelve hour and 1 day post EMP exposure associative learning was reduced significantly compared with sham control (p<0.05) but recovered at 2 d post EMP exposure. (2) Compared with the sham control, lipid peroxidation of brain tissue and chemiluminescence (CL) intensity increased significantly (p<0.05), while the activity of the antioxidant enzymes Superoxide Dismutase [SOD], Glutathione [GSH], Glutathione Peroxidase [GSH-Px], Catalase [CAT]) decreased significantly (p<0.05) at 3 h, 6 h, 12 h and 1 d post EMP exposure. All these parameters recovered at 2 d post EMP exposure. (3) No significant differences between the sham control group and EMP exposed group were observed in serum cholesterol and triglycerides. (4) Pretreatment of mice with TMG showed protective effects to EMP exposure.
EMP exposure significantly decreased associative learning in mice and TMG acted as an effective protective agent from EMP exposure. This mechanism could involve an increase of oxidative stress in brain by EMP exposure.
研究电磁脉冲（EMP）对小鼠联想学习的影响，并检验其初步作用机制。
采用锥形平行板千兆赫横电磁（GTEM）细胞和喇叭形矩形同轴传输线，使雄性 BALB/c 小鼠暴露于 EMP（峰值强度 400 kV/m，上升时间 10 ns，脉冲宽度 350 ns，0.5 Hz，共 200 个脉冲）。同时设置假暴露对照小鼠。分别检测小鼠的联想学习、脑内氧化应激、血清化学以及生育酚单葡萄糖苷（TMG）的保护作用。
（1）EMP 暴露后 12 h 和 1 d，与假对照相比，小鼠的联想学习明显降低（p<0.05），但在 EMP 暴露后 2 d 恢复。（2）与假对照相比，脑组织脂质过氧化和化学发光（CL）强度明显增加（p<0.05），而抗氧化酶超氧化物歧化酶（SOD）、谷胱甘肽（GSH）、谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶（CAT）的活性明显降低（p<0.05），EMP 暴露后 3 h、6 h、12 h 和 1 d。所有这些参数在 EMP 暴露后 2 d 恢复。（3）假对照和 EMP 暴露组的血清胆固醇和甘油三酯均无显著差异。（4）TMG 预处理对 EMP 暴露具有保护作用。
EMP 暴露明显降低了小鼠的联想学习能力，TMG 是 EMP 暴露的有效保护剂。这种机制可能涉及 EMP 暴露引起的脑内氧化应激增加。
