comparing the effects of long-term exposure to extremely low-frequency electromagnetic fields with different values on learning, memory, anxiety, and β-amyloid deposition in adult rats

Introduction: extremely low-frequency electromagnetic fields (elf-emfs) have gatheredsignificant consideration for their possible pathogenicity. however, their effects on the nervoussystem’s functions were not fully clarified. this study aimed to assay the impact of elf-emfswith different intensities on memory, anxiety, antioxidant activity, β-amyloid (aβ) deposition,and microglia population in rats.methods: fifty male adult rats were randomly separated into 5 groups; 4 were exposed toa flux density of 1, 100, 500, and 2000 microtesla (μt), 50 hz frequency for one h/day fortwo months, and one group as a control group. the control group was without elf-emfstimulation. after 8 weeks, passive avoidance and elevated plus maze (epm) tests wereperformed to assess memory formation and anxiety-like behavior, respectively. total free thiolgroups and the index of lipid peroxidation were evaluated. additionally, for detection of aβdeposition and stained microglia in the brain, anti-β-amyloid and anti-iba1 antibodies were used.results: the step-through latency in the retention test in elf-emf exposure groups (100500& 2000 μt) was significantly greater than the control group (p<0.05). furthermore, thefrequency of the entries into the open arms in elf-emf exposure groups (especially 2000μt) decreased than the control group (p<0.05). no aβ depositions were detected in thehippocampus of different groups. an increase in microglia numbers in the 100, 500, and 2000μt groups was observed compared to the control and one μt group.conclusion: exposure to elf-emf had an anxiogenic effect on rats, promoted memory, andinduced oxidative stress. no aβ depositions were detected in the brain. moreover, the positiveimpact of elf-emf was observed on the microglia population in the brain.