Protein expression and corresponding gene expression of occludin, ZO-1 and two metalloproteinases as well as the enzyme activity of the metalloproteinases were examined. Occludin is a transmembrane protein that restricts the permeability at the tight junctions. ZO-1 links transmembrane proteins to the actin cytoskeleton. A disruption of these combinations as well as an increased enzyme activity of metalloproteinases are associated with an increased permeability of the blood brain barrier.
Rats were sham exposed or exposed and analyzed 0.5, 1, 3, 6 or 12 hours post exposure (n=8 per group).
Exposure duration: 200 seconds
|Sham exposure||A sham exposure was conducted.|
|electric field strength||200 kV/m||-||-||-||-|
The permeability of the blood brain barrier was significantly increased 0.5, 1 and 3 hours after exposure when compared to the sham exposed group. After exposure, protein expression and gene expression of occludin and ZO-1 were significantly decreased compared to the control group, while the expression of the metalloproteinases was significantly increased. Additionally, the enzyme activity of the metalloproteinases was significantly increased compared to the sham exposed group.
12 hours after the exposure, the values recovered and no changes in the permeability, protein expression, gene expression and enzyme activity were observed in comparison to the sham exposed group.
The authors conclude that PEMF exposure could transiently alter the permeabilty of the blood brain barrier and that this effect was related to modified expression levels of occludin, ZO-1 and metalloproteinases.