scholarly journals The Effect of 12 Hz Extremely Low-Frequency Electromagnetic Fields on Visual Memory of Male Macaque Monkeys

Author(s):  
Masoomeh Kazemi ◽  
◽  
Hamed Aliyari ◽  
Elaheh Tekieh ◽  
Hassan Tavacoli ◽  
...  

Introduction: Today, humans leave in a world surrounded by electromagnetic fields. Numerous studies have been carried out to discover the biological, physiological, and behavioral effects of electromagnetic fields on humans and animals. Given the biological similarities between monkeys and humans, the goal of the present research was to examine Visual Memory (VM), hormonal, genomic, and anatomic changes, and changes of the amygdala function in the male rhesus macaques who exposed to extremely low-frequency magnetic fields (ELF/MF). Materials and methods: Four male Rhesus Macaques (Macaca mulatta) were used. For the behavioral tests the animals were needed to be fasting for 17 hours, and for the behavioral tests such as visual memory, cooperation of the animal was necessary. Using the radiation protocol, two of the monkeys were exposed to 12-Hz electromagnetic fields with a magnitude of 0.7 microtesla (electromagnetic radiation) four hours a day for a month. Before and after the exposure, a visual memory test was conducted using a coated device (visible reward) on a movable stand. Ten mL of blood was obtained from the femoral artery of the monkeys and half of it was used to examine cortisol serum levels using MyBioSource kits (made in the USA). The other half of blood samples were used to extract lymphocytes for assaying expressions of Glucocorticoid Receptor (GR) genes before and after radiation using the PCR method. Anatomic studies of the amygdala were carried out based on pre- and post-radiation Magnetic Resonance Imaging (MRI). Findings: Research results indicated that visual memory in male primates increased significantly at the 12Hz frequency. Hormonal analysis at the 12Hz frequency showed a decrease in cortisol serum levels. However, visual memory and serum cortisol levels did not change considerably in male primates in the control group. There was no considerable amygdala volumetric difference at the 12 Hz frequency. The expression of the GR genes decreased at 12Hz compared to the control group. Conclusion: In short, these results indicated that ELF may have a beneficial value for memory enhancement as indicated by the fact that exposure to the 12 HZ ELF can enhance visual memory. This may be due to a decrease in plasma cortisol, and/or expression of GR genes. Moreover, direct involvement of the amygdala in this regard cannot be recommended.

Author(s):  
Nafiseh Faraji ◽  
◽  
Iraj Salehi ◽  
Akram Alizadeh ◽  
Arash Pourgholaminejad ◽  
...  

Background: Extremely low-frequency electromagnetic fields (ELF-EMFs) have gathered significant consideration for their possible pathogenicity. However, their effects on nervous system functions were not fully clarified. In this study, our aim was to assay the effect of ELF-EMFs with different intensity on memory, anxiety, antioxidant activity, beta amyloid (Aβ) deposition and microglia population in rats. Materials and Methods: Fifty male adult rats were randomly separated into 5 groups; four groups exposed to a flux density of 1, 100, 500 and 2000 microtesla (µT), 50 Hertz (Hz) frequency for 1h/day for 2 months and one group as a control group. The control group were without ELF-EMF stimulation. After 8 weeks, passive avoidance and elevated plus maze (EPM) tests was performed to assess memory formation and anxiety-like behavior, respectively. Total free thiol groups and the index of lipid peroxidation were assessed. Also, for detection of β-Amyloid deposition and stained microglia in the brain, anti-β-amyloid and anti-Iba1 antibodies were used. Results: In the ELF-EMF exposure groups, the step-through latency was significantly greater in the retention test (100,500, and 2000 µT) than in the control group (P<0.05). Also, the percentage of the entries into the open arms in ELF-EMF exposure groups (especially 2000 µT) decreased than control group (P <0.05). No β-Amyloid depositions were detected in the hippocampus of different groups. An increase in microglia numbers in the 100, 500 and 2000 µT groups was observed in compare to the control and 1 µT group. Conclusion: Exposure to ELF-EMF had an anxiogenic effect on rats and promoted memory and also induced oxidative stress. No β-Amyloid depositions were detected in the brain. Also, positive effect of ELF-EMF was observed on population of microglia population in the brain.


2005 ◽  
Vol 58 (11-12) ◽  
pp. 609-613 ◽  
Author(s):  
Dusko Knezevic

Introduction The immune system plays a major role in the origin, growth and evolution of tumors: factors that decrease the immune response in any way can cause higher tumor incidence and its faster or uncontrolled growth and evolution. Material and methods The research included 18 healthy male Han- NMRI mice, weighing between 25 and 30g, with ten-day-old tumor deposits, divided into three groups consisting of six mice each. The first group was continuously exposed to extremely low frequency electromagnetic fields (intensity 70-320 ?T). The second group was treated with high doses of Corticosteroids (dexamethasone). The control group was not treated with Corticosteroids, nor was exposed to extremely low frequency electromagnetic fields. The exposure period lasted for ten days. The criteria used to evaluate tumor immunity were: histologicai findings of leukocyte infiltration around the tumor cells and white blood cell count. The control group presented with excellent immune response to tumor cells. Lymphoplasmacytic infiltrates widely surrounded the tumor. Numerous tumor cells showed signs of cell death. The results showed that exposure of animals to high doses of glucocorticoids resulted in extremely decreased leukocyte infiltration in the tumor tissue (single lymphocytes), while exposure to extremely low frequency electromagnetic fields significantly-decreased leukocyte infiltration in comparison to the control group. Comparison of white blood cell count in treated groups revealed that the white blood cell count in both treated groups was decreased, compared with the control group. Conclusion Extremely low frequency electromagnetic fields significantly suppress the immune response to tumor cells. Dexamethasone treatment resulted in almost complete absence of immune response to tumor cells. Electromagnetic fields and dexamethosone both decrease the while blood cell count. .


2013 ◽  
Vol 6 (1) ◽  
pp. 84-86 ◽  
Author(s):  
Inmaculada Tasset ◽  
Aleyda Pérez-Herrera ◽  
Francisco J. Medina ◽  
Óscar Arias-Carrión ◽  
René Drucker-Colín ◽  
...  

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