Department of Neuroanatomy and Molecular Brain Research, Ruhr-University Bochum, Bochum, Germany.
PLoS One. 2011 May 5;6(5):e19437. doi: 10.1371/journal.pone.0019437.
Harmful effects of electromagnetic fields (EMF) on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF) signals of the Universal Mobile Telecommunications System (UMTS) to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH) and on hippocampal derived synaptic long-term plasticity (LTP) and depression (LTD) as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR) as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass) did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg). The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg) cannot be excluded.
电磁场 (EMF) 对人类和啮齿动物认知和行为特征的有害影响一直存在争议，并引起了人们对 EMF 对大脑一般功能的不良影响的持续关注。在本研究中，我们将射频 (RF) 信号应用于全脑暴露的雄性 Wistar 大鼠，以详细阐述其对应激激素释放 (皮质酮; CORT 和促肾上腺皮质激素; ACTH) 和海马衍生的突触长时程可塑性 (LTP) 和抑郁 (LTD) 的潜在影响，作为记忆存储和记忆巩固的电生理学标志。暴露是通过计算机控制的，提供盲条件。作为应用质量相关耗散 RF 功率的衡量标准，名义脑平均比吸收率 (SAR) 在 120 分钟内为 0、2 和 10 W/kg。无论 EMF 暴露如何，与 cage 暴露的动物相比，CORT 和 ACTH 水平显著升高，这与海马 LTP 和 LTD 中的场电位斜率和幅度普遍降低相对应。在 SAR 暴露 2 W/kg（整个大脑 2.3 克组织质量的平均值）的动物中，LTP 和 LTD 实验与假暴露组没有差异。相比之下，在高功率 SAR（10 W/kg）下，LTP 和 LTD 明显减少。结果表明，2 W/kg 的速率对 LTP 和 LTD 没有不利影响，而 10 W/kg 的速率会对电生理参数产生显著影响，这可以与应激引起的背景明显区分开来。我们的研究结果表明，SAR 在 2 W/kg 范围内的 UMTS 暴露对记忆存储和记忆巩固的关键标志物没有危害，然而，不能排除 UMTS 在高能量吸收率 (10 W/kg) 下的影响。
