Influence of extremely low frequency magnetic fields on Ca2+ signaling and NMDA receptor functions in rat hippocampus

Manikonda, Pavan Kumar; Rajendra, P; Devendranath, D.; Gunasekaran, B.; Channakeshava,; Aradhya, R. S. Shivakumara; Sashidhar, R.B.; Subramanyam, Chakrapani

doi:10.1016/j.neulet.2006.11.048

Cited by 129 publications

(89 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, such exposure resulted in increased physical activity significantly at 50 µT and 100 µT (p ≤ 0.001) compared to sham-exposed controls (previously described in Manikonda et al 2007). In the present investigation, the changes in oxidative stress markers were perceived in the ELF-MF exposed animals as compared to sham controls, as described below.…”

Section: Resultssupporting

confidence: 58%

“…Earlier studies on developing chick embryos reported that power line frequency magnetic fields alter neurochemical parameters such as tyrosine, glutamine, norephinephrine levels and the activity of glutamate synthase in developing chick embryos (Rajendra et al 2004). The studies have also reported that ELF-MF decreased N-methyl D-Aspartic Acid (NMDA) receptor binding affinity and altered calcium signaling enzymes (Manikonda et al 2007). In continuation of these neurochemical observations, this communication evaluates parameters related to oxidative stress on the hippocampus (associated with learning and memory), cerebellum (responsible for regulation/ coordination of movement and balance) and cortex (involved in higher brain functions of thought and action) in rodent brains exposed to long-term ELF-MF.…”

Section: Introductionmentioning

confidence: 96%

“…In view of the above cited investigations, it is evident that no single study has been definite while evaluating biological effects due to MF exposure (EMF RAPID Program 2004); we have earlier conducted numerous MF exposure studies involving different biological systems that includes in vitro (cell cultures) as well as in vivo (animals, plants and developing embryos) models (Rajendra et al 2004(Rajendra et al , 2005(Rajendra et al , 2012Manikonda et al 2007) to obtain holistic information. The magnetic field intensities selected for the present study were based on the data collected from field surveys conducted in India by Ultra High Voltage Research Laboratory of Central Power Research Institute (CPRI), Government of India (Final Technical Report 2000, Identification No.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Extremely low frequency magnetic fields induce oxidative stress in rat brain

Pk¹,

Rajendra²,

Devendranath³

et al. 2014

gpb

Self Cite

View full text Add to dashboard Cite

Abstract. The present investigation was conducted to understand the influence of long-term exposure of rats to extremely low frequency magnetic fields (ELF-MF), focusing on oxidative stress (OS) on different regions of rat's brain. Male Wistar rats (21-day-old) were exposed to ELF-MF (50 Hz; 50 and 100 µT) for 90 days continuously; hippocampal, cerebellar and cortical regions from rats were analyzed for (i) reactive oxygen species (ROS), (ii) metabolites indicative of OS and (iii) antioxidant enzymes. In comparison to control group rats, the rats that were continuously exposed to ELF-MF caused OS and altered glutathione (GSH/GSSG) levels in dose-dependent manner in all the regions of the brain. Accumulation of ROS, lipid peroxidation end products and activity of superoxide dismutase in different regions was in the descending order of cerebellum > hippocampus > cortex. Decrement in GSH/GSSG levels and increment in glutathione peroxidase activity were in the descending order of hippocampus > cerebellum > cortex. The continuous exposure to ELF-MF caused OS in all the examined regions of brain more significantly at 100 µT than at 50 µT. Varied influences observed in different regions of the brain, as documented in this study, may contribute to altered metabolic patterns in its related regions of the central nervous system, leading to aberrant neuronal functions.

show abstract

Section: Resultssupporting

confidence: 58%

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Extremely low frequency magnetic fields induce oxidative stress in rat brain

Pk¹,

Rajendra²,

Devendranath³

et al. 2014

gpb

Self Cite

View full text Add to dashboard Cite

show abstract

“…Among these, the effects on synaptic plasticity, neurotransmitter oscillation, life of neuronal cells, learning, and memory are especially remarkable. In view of the current studies, it can be said that overuse of cell phones may particularly cause longterm significant changes in the structure and function of brain nerve cells (15).…”

Section: Discussionmentioning

confidence: 83%

The effect of caffeine on neuron number of rats exposed to 900-MHz electromagnetic field

2018

Turk J Vet Anim Sci

View full text Add to dashboard Cite

IntroductionRecently, an increasing number of studies have investigated whether an electromagnetic field (EMF) has harmful effects on human health. The number of masses influenced by the radiofrequency waves radiated by base stations and cell phones increases as time goes by. In particular cell phones, which provide useful services to humans, are thought to have many harmful effects (1). The effects of EMF on the tissues and organs of human beings are frequently investigated (2). The most outstanding of these are studies that present the effects of EMF on central nervous system diseases and brain functions.Radio waves that occupy the frequency range from 3 kHz to 300 GHz are forms of electromagnetic energy. The devices working in this frequency range form an impact area called radiofrequency EMF. Cell phones operate in the frequency range of 800-2600 MHz. The third-and fourthgeneration mobile phones use microwaves of 1800-2100 MHz whereas second-generation phones operate at 900 MHz, which is still the most commonly used mobile communication system (3).Since developing tissues and organs are very sensitive to harmful agents, the potential harmful effects of microwaves on children have been assessed in the agenda of the World Health Organization since 2006, and continuous studies are being conducted on the subject (4). A wide-scale casecontrol study conducted by two different research centers has examined the relationship between brain tumors and cell phone use. One of these studies found a significant association between cell phone use and malignant brain tumors (4). On the other hand, another study reported that cell phone use of 10 years did not increase the risk for acoustic neuroma, and it was also mentioned that 10year cell phone use was not long enough for neuroma development. (5). Exposure to 900-MHz EMF was shown to decrease the number of Purkinje cells in the cerebellum (3).Caffeine (1,3,7-trimethylxanthine), is a psychostimulant consumed in great amounts in Western countries (6). This purine alkaloid, which has a formula of C 8 H 10 N 4 O 2 , is found in coffee, tea, energy drinks, various soft drinks, and cacao. In addition, it is naturally found in the fruits, seeds, and leaves of many plants (7).Although it changes from person to person, people generally consume some caffeine every day without even realizing it. A brewed coffee drink of 437 mL contains an average of 188 mg of caffeine. The caffeine concentration in coffee beans can differ between 0.01 mg/g and 19.9 mg/g.

show abstract

“…For instance it is reported that neither short term (7 days), Nor long term exposure to 25-50Hz fields did not make a change in motor activity, but 50 Hz field exposure will decrease recognition of new arm of the Y maze [3]. It is suggested that EMFs can make changes in calcium ion homeostasis in neuronal tissues and it was found that exposure to extremely low frequency EMFs increased Ca ions levels in Hippocampal regions cells [4]. In this study the effect of extremely low frequency (50 Hz, 8 mT) electromagnetic fields on learning in male mice was examined.…”

Section: Introductionmentioning

confidence: 99%

Mice Learning After 30 Minutes Exposure to Electromagnetic Field

Forooz¹

2017

MOJT

View full text Add to dashboard Cite

The aim of this experimental study was to investigate the effect of extremely low frequency (50 Hz, 8 mT) electromagnetic fields on earning in mice. The learning was evaluated with passive avoidance learning and after each learning session, an animal in experimental group was exposed to an 8mT, 50Hz electromagnetic field for 30 minutes. The results showed that exposure to a 50 Hz, 8mT electromagnetic field for 30 minutes after the animal's learning has devastating effects on avoidance learning in mice (p<0.05). IntroductionRecent studies in Behavioral and psychological fields have shown that exposure to electromagnetic fields (EMFs) can change human cognitive functions and behaviors of animals [1,2]. For instance it is reported that neither short term (7 days), Nor long term exposure to 25-50Hz fields did not make a change in motor activity, but 50 Hz field exposure will decrease recognition of new arm of the Y maze [3]. It is suggested that EMFs can make changes in calcium ion homeostasis in neuronal tissues and it was found that exposure to extremely low frequency EMFs increased Ca ions levels in Hippocampal regions cells [4]. In this study the effect of extremely low frequency (50 Hz, 8 mT) electromagnetic fields on learning in male mice was examined. MethodAdult male mice (25-30 g) were housed five per cage in a room with natural light cycle and constant temperature (24±2C). Food and water were available ad libitum. All procedures were conducted in agreement with the National Institutes of Health Guide for care and use of laboratory animals. In this study, to measure learning or acquisition of information, mice were evaluated with inhibitory (passive) avoidance task. Passive avoidance learning box is a wooden box with dimensions (30*30*40cm) and the floor of the 29 steel bars, the diameter of 0.3 cm. Bars are away from each other 1 cm. A wooden platform (4 * 4 * 4cm) is placed in the middle floor of the box. By an electric shock (1 Hz, 0.5 seconds, and 50 V, DC) can be controlled irritating situation (Grass S44-Quincy, Massachusetts.USA). In the learning stage, the animal was gently placed on the small wooden platform in the middle of box. Animal's natural tendency to coming down from the platform, make it to move in space of larger wooden box immediately. A 15 seconds electric shock was given as soon as animal came down from the platform and placed on the floor of the box. So despite his natural tendency, mice learn to stay on platform. After 24 hours and in test session, avoidance learning with step-down latency was calculated [5] (Hiramatsu, Sasaki & Kameyama (1995). Electromagnetic field was applied in a room adjacent to that used for behavioral experiments. A sinusoidal magnetic field was created using a round coil electromagnet made from a 1000 turned copper wire (0.50 mm). The electromagnet was supplied with a sinusoidal waveform signal generator (GFG-8019G, Good Will instrument Co.). Then amplifier output droved to coil, producing an ELF of 8 mT at the center of the coil. The desired intensit...

show abstract

Influence of extremely low frequency magnetic fields on Ca2+ signaling and NMDA receptor functions in rat hippocampus

Cited by 129 publications

References 34 publications

Extremely low frequency magnetic fields induce oxidative stress in rat brain

Extremely low frequency magnetic fields induce oxidative stress in rat brain

The effect of caffeine on neuron number of rats exposed to 900-MHz electromagnetic field

Mice Learning After 30 Minutes Exposure to Electromagnetic Field

Contact Info

Product

Resources

About