Department of Histology and Embryology, Faculty of Medicine, Niğde Ömer Halisdemir University, Niğde, Turkey.
Department of Clinical Medicine, Core Centre for Molecular Morphology, Section for Stereology and Microscopy, Aarhus University Hospital, Aarhus C, Denmark.
J Chem Neuroanat. 2019 Nov;101:101681. doi: 10.1016/j.jchemneu.2019.101681. Epub 2019 Aug 26.
The aim of this study was to investigate qualitative and quantitative changes in pyramidal and granule neurons in the male rat hippocampus after exposure to a continuous 900-megahertz (MHz) electromagnetic field (EMF) for 25 days during early and mid-adolescence. Three-week-old (21 day) healthy Sprague Dawley male rats were divided equally into control (CON), pseudo-exposed (PEX) and EMF groups. EMF rats were exposed to a 900-MHz EMF in an EMF-application cage, while the PEX rats were placed in the same cage without being exposed to EMF. No procedure was performed in CON. EMF was applied for 1 h/day, every day for 25 days. Following the 900-MHz EMF and pseudo-exposed applications, behavioral tests were performed for seven days. Then, all animals were euthanized and their brains were removed. Following histological tissue procedures, sections were taken from tissues and stained with toluidine blue. The optical fractionation technique was performed to estimate the pyramidal neuron numbers in the CA1, CA2-3 and hilus regions of the hippocampus and granule neuron numbers in the dentate gyrus region. Our findings indicated that the number of pyramidal and granule neurons in the hippocampus of the EMF group was statistically higher than PEX. Furthermore, the histopathological results showed that the cytoplasm of pyramidal (in the hilus, CA1, CA2 and CA3 region) and granular (in the dentate gyrus region) cells at the hippocampus were disrupted, as evident by intensive staining around cytoplasm and some artifacts were detected in the EMF group. In addition, statistical comparisons of the mean body weights and brain weights of the study groups revealed no significant differences. There was no statistically significant difference between the PEX and EMF groups in terms of temperature (p > 0.05) or humidity (p > 0.05) in the cages. In conclusion, higher numbers of both pyramidal and granule neurons were found in the male rat hippocampus after continuous 900-MHz EMF treatment.
本研究旨在探讨雄性大鼠海马锥体神经元和颗粒神经元在青春期早期和中期连续暴露于 900 兆赫兹（MHz）电磁场（EMF）25 天后的定性和定量变化。将 3 周龄（21 天）健康的 Sprague Dawley 雄性大鼠等分为对照组（CON）、假暴露组（PEX）和 EMF 组。EMF 组大鼠在 EMF 应用笼中暴露于 900MHz EMF，而 PEX 组大鼠被放置在相同的笼子中而不暴露于 EMF。CON 组不进行任何操作。EMF 每天应用 1 小时，连续 25 天。在应用 900MHz EMF 和假暴露后，进行了为期 7 天的行为测试。然后，所有动物被安乐死并取出大脑。进行组织学组织处理后，从组织中取出切片并用甲苯胺蓝染色。采用光分割技术估计海马 CA1、CA2-3 和齿状回区的锥体神经元数量以及齿状回区的颗粒神经元数量。我们的研究结果表明，与 PEX 相比，EMF 组海马中的锥体和颗粒神经元数量明显更高。此外，组织病理学结果显示，海马中锥体（在齿状回、CA1、CA2 和 CA3 区的神经节）和颗粒（在齿状回区）细胞的细胞质受到破坏，可见细胞质周围染色加深，并且在 EMF 组中检测到一些伪影。此外，研究组间平均体重和脑重的统计学比较显示无显著差异。在笼中，PEX 和 EMF 组之间的温度（p＞0.05）或湿度（p＞0.05）无统计学差异。总之，在雄性大鼠海马中连续暴露于 900MHz EMF 后，发现锥体和颗粒神经元的数量均增加。
