To investigate the effects of a 2.45 GHz electromagnetic field exposure on the brain cortex and the dorsal root ganglion of rats, as well as the possible protective effects of melatonin administration.
4 groups (n=8 per group) were examined: 1.) cage control, 2.) sham exposure + daily injection of saline, 3.) exposure and 4.) exposure + daily injection of melatonin (10 mg/kg).
Before the animals were killed, an EEG was recorded. Afterwards, brain homogenates and the dorsal root ganglion were investigated for signs of oxidative stress. Additionally, in the dorsal root ganglion, the intracellular calcium concentration was determined and the patch-clamp technique was conducted.
|Exposure duration||continuous for 1 h/day on 30 days|
|Repetition frequency||217 Hz|
|Distance between exposed object and exposure source||1 m|
|Setup||rats kept in 15 cm long cylindrical constrainers with a diameter of 5 cm; 8 constrainers positioned radially on a groundplate with the antenna in the center; rats placed with their heads near the antenna|
|Sham exposure||A sham exposure was conducted.|
In general, no differences were found between the cage control (group 1) and the sham exposed group (group 2).
In the exposed group (group 3), the number of spikes in the EEG was increased compared to the control groups (group 1+2). However, no differences occurred in the EEG between the exposed group treated with melatonin (group 4) and the control groups (groups 1+2).
In the dorsal root ganglia of exposed rats (group 3), the cell viability was significantly decreased compared to the control groups (group 1+2). In contrast, there was no difference in the cell viability between the melatonin treated exposure group (group 4) and the control groups (groups 1+2). Additionally, in the exposed group (group 3), the level of lipid peroxidation and the intracellular calcium release were increased in comparison to the control groups (groups 1+2). Again, no differences in the level of lipid peroxidation and the intracellular calcium release were found between the melatonin treated exposure group (group 4) and the control groups (group 1+2). The current densities of the neurons were higher in the exposed group (group 3) than in the control groups (groups 1+2).
In brain homogenates of exposed rats, treated with melatonin (group 4), an increased concentration of vitamin E was found, whereas the concentration of vitamin E in the other groups (groups 1+2+3) did not change.
Remaining brain homogenate and dorsal root ganglion antioxidant values were not affected by exposure or melatonin administration.
The authors conclude that exposure to a wireless device of 2.45 GHz could induce oxidative stress in the dorsal root ganglion and that melatonin could prevent such a reaction.