Rats were divided into 4 groups: 1) exposure of healthy rats (n=15), 2) exposure of Alzheimer's disease model rats (n=14), 3) non-exposed Alzheimer's disease model rats (n=15), 4) non-exposed healthy rats (n=13; control group).
Rats were examined up to 5 days after termination of exposure.
|Exposure duration||continuous for 24 hours/day for 60 days|
|Chamber||boxes with 20 cm height and 50 cm square bottom|
|Setup||two parallel coaxial circular coils with 70 cm height and 140 cm diameter were used and two modular breeding devices each comprising 4 boxes with 8 animals per box were used; MF intensity in breeding device was attenuating ringlike but was unchanged longitudal along the axis of the coils|
|Additional info||non-exposed animals were kept in a separate room on the same floor as the exposed animals; both rooms shared the same ventilation system and humidity, light, temperature and air quality of the both rooms was equal|
All rats exposed to the magnetic field (groups 1 and 2) showed a significantly delayed weight gain compared to non-exposed rats (3 and 4).
In the Morris water maze, a partial improvement of the spatial memory and learning was observed in Alzheimer's disease model rats exposed to the magnetic field (group 2) compared to Alzheimer's disease model rats without exposure (group 3).
Histopathological damages were found in groups 1-3 15 minutes after the end of exposure, but the groups exposed to the magnetic field (groups 1 and 2) showed a partial recovery after 5 further days.
The expression rates of several proteins were significantly different in the groups 1-3 compared to the control group and in exposed Alzheimer's disease model rats (group 2) compared to non-exposed model rats (group 3). Identified proteins are involved in synaptic transmission, oxidative stress, protein degradation, energy metabolism, Tau protein aggregation and inflammation processes.
The authors conclude that exposure to a 50 Hz magnetic field could improve cognitive and histopathological symptoms of Alzheimer's disease model rats and that several molecular clues for further research could be identified.