Male rats were divided into the following groups (n=16, respectively): exposure to a magnetic flux density of 1) 1 µT, 2) 100 µT, 3) 500 µT, 4) 2000 µT and 5) sham exposure. After one month of exposure, blood samples were collected (pre-immunization phase). Then each rat received 100 μg of human serum albumin to stimulate the immune system on days 31, 44, and 58 of the exposure period. On day 61, the end of the exposure period, rats were sacrificed and second blood samples were taken (post-immunization phase).
|Chamber||2 hours/day for 60 days|
|Setup||solenoids were made of polyvinyl chloride (PVC) tubes (2 meters long and 40 centimeters in diameter); different magnetic field flux densities were produced by combinations of different turns of wires, electrical potential and currents; temperature and humidity were maintained constant during exposure using fan-controlled air circulation|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||1 µT||-||measured||-||-|
In the pre-immunization phase, serum levels of pro-inflammatory cytokines interleukin-9 and TNF-α were significantly decreased in group 2 (100 µT) and groups 2-4 (100-2000 µT), respectively, compared with the sham exposure group. The level of interleukin-10, however, was significantly increased in groups 1 (1 µT) and 2 compared to the sham exposure group. In the post-immunization phase, serum levels of interleukin-9 and TNF-α were significantly decreased in groups 1 and 2 compared with the sham exposure group, while interleukin-10 did not show any differences.
The levels of interleukin-9 and TNF-α were significantly increased in groups 2-5 in the post-immunization phase compared to the pre-immunization phase. The levels of interleukin-10 also increased significantly in group 4 and 5 (sham exposure group) in the post-immunization phase compared to pre-immunization.
The authors conclude that exposure to a 50 Hz magnetic field may have anti-inflammatory effects in rats, by down-modulation of pro-inflammatory cytokines and induction of anti-inflammatory cytokines.