[Effect of extremely low frequency magnetic field on the focal brain injury in rats].
OBJECTIVE
To examine the effect of extremely low frequency magnetic field (ELMF) on the brain trauma in rats.


METHODS
Using the focal left-brain cortex contusion model, rats were divided into two groups, ELMF group (3 d and 8 d) and control group (3 d and 8 d), ELMF stimulations were given after the brain trauma provided by a coil (phi 10 cm) which was driven by 15 Hz sinusoidal signals so that ELMF strength of 18 mT at the midpoint was obtained. The morphologic changes were observed in these groups.


RESULTS
As compared with the control group, the extent of the inflammatory reaction and the neuronal damage was apparently lighter in magnetic field group, especially in 8 d group. At the far away region from the injured brain area, the neuronal shape was changed, and the amount of this special neurocyte was larger in magnetic field group than that in control group, especially in 8 d group.


CONCLUSIONS
ELMF stimulation in the present study may alleviate the brain injury reaction. Attention should be paid to the role of the special neurocyte during the brain injury.
Institute of Space Medico-Engineering, Beijing, China. lunzhao@263.net
Lun
L
Zhao
De-ming
DM
Zhao
Jin-he
JH
Wei
Yu-qing
YQ
Wang
Zeng-ming
ZM
Huang
D000818:Animals; D001930:Brain Injuries / Q000473:pathology* / Q000517:prevention & control*; D004574:Electromagnetic Fields; D007249:Inflammation / Q000473:pathology / Q000517:prevention & control; D008280:Magnetics / Q000627:therapeutic use*; D009474:Neurons / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar