ABSTRACT Subchronic effect of a weak combined magnetic field (MF), produced by superimposing a constant component, 42 µT and an alternating MF of 0.08 µT, which was the sum of two frequencies of 4.38 and 4.88 Hz, was studied in olfactory bulbectomized (OBE) and transgenic Tg (APPswe, PSEN1) mice, which were used as animal models of sporadic and heritable Alzheimer’s disease (AD) accordingly. Spatial memory was tested in a Morris water maze on the following day after completion of training trials with the hidden platform removed. The amyloid-β (Aβ) level was determined in extracts of the cortex and hippocampus of mice using a specific DOT analysis while the number and dimensions of amyloid plaques were detected after their staining with thioflavin S in transgenic animals. Exposure to the MFs (4 h/day for 10 days) induced the decrease of Aβ level in brain of OBE mice and reduced the number of Aβ plaques in the cortex and hippocampus of Tg animals. However, memory improvement was revealed in Tg mice only, but not in the OBE animals. Here, we suggest that in order to prevent the Aβ accumulation, MFs could be used at early stage of neuronal degeneration in case of AD and other diseases with amyloid protein deposition in other tissues.

中文翻译：

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弱组合静态和极低频交变磁场对两种阿尔茨海默病动物模型空间记忆和脑淀粉样蛋白β的影响

摘要 通过叠加恒定分量 42 µT 和 0.08 µT 交替 MF（4.38 和 4.88 Hz 的两个频率之和）产生的弱组合磁场 (MF) 的亚时效效应在嗅球切除术 (OBE) 中进行了研究。 ) 和转基因 Tg (APPswe, PSEN1) 小鼠，它们相应地用作散发性和遗传性阿尔茨海默病 (AD) 的动物模型。在完成训练试验后的第二天，在移除隐藏平台的情况下，在莫里斯水迷宫中测试空间记忆。使用特定的 DOT 分析测定小鼠皮层和海马提取物中的淀粉样蛋白 - β (Aβ) 水平，而在转基因动物中用硫代黄素 S 染色后检测淀粉样蛋白斑块的数量和尺寸。暴露于 MFs（4 小时/天，持续 10 天）诱导 OBE 小鼠大脑中 Aβ 水平的降低，并减少 Tg 动物皮层和海马中 Aβ 斑块的数量。然而，仅在 Tg 小鼠中显示出记忆改善，而在 OBE 动物中未显示。在这里，我们建议为了防止 Aβ 积累，可以在神经元变性的早期阶段使用 MF，以防 AD 和其他组织中淀粉样蛋白沉积的其他疾病。