ID Number		2101
Study Type		In Vivo
Model		1 Hz high peak pulsed exposure to rats and analysis of blood brain barrier and blood-testis barrier permeability.
Details		Sprage Dawley rats were exposed to 1 Hz pulsed at either 200 or 400 pulses per second at 200 kV/m. Following exposure at 0.5, 1, 3, 6, or 12 hours, blood brain barrier permeability was evaluated using transmission electron microscopy and immunohistochemistry to follow lanthanum nitrate and endogenous albumin markers. The authors report significant leakge to the tight junction, basal lamina, and pericapillary tissue in a a dose dependent manner that started after 1 hour, reached a peak at 3 hours, and recovered after 12 hours post exposure. AUTHORS' ABSTRACT: Zhang et al. 2012 (IEEE #6880): Objective To investigate the expression of occludin, ZO1, MMP2, and MMP9 in cerebral microvasculature following Pulse Electromagnetic Field (PEMF) induced BBB permeability change. Methods SpragueDawley rats were randomized into PEMF and sham exposed groups (n=8). After exposure to PEMF at 0.5, 1, 3, 6, and 12 h, BBB permeability was measured by EvansBlue extravasation. The expression of occludin, ZO1, MMP2, and MMP9 were detected by realtime quantitative reverse transcriptase PCR and western blotting. MMP2 and MMP9 activity were detected by EnzChek gelatinase assay. Results Compared with the sham group, PEMF exposure led to increased permeability of the BBB to EB, which was prolonged after exposure. BBB permeability became progressively more severe, and recovered at 6 h. The gene and protein expression of occludin and ZO1 were significantly decreased, while MMP2 and MMP9 expression were significantly increased after exposure to PEMF. All levels of expression recovered 12 h following PEMF. Conclusion Changes to BBB permeability were related to the alteration expression of tight junction proteins and matrix metalloproteinase after exposure to PEMF. AUTHORS' ABSTRACT: Zhou et al. 2013 (IEEE #6881): bloodbrainbarrier (BBB) model. Methods An in vitro BBB model, established by coculturing brain microvascular endothelial cells (BMVEC) and astroglial cells (AC) isolated from rat brain, was exposed to EMP at 100 kV/m and 400 kV/m, respectively. Permeability of the model was assayed by measuring the transendothelial electrical resistance (TEER) and the horseradish peroxidase (HRP) transmission at different time points. Levels of BBB tight junctionrelated proteins were measured at 0, 1, 2, 4, 8, 12, 16, 20, 24 h after EMP exposure by Western blotting. Results The TEER level was lower in BBB model group than in control group at 12 h after EMP, exposure which returned to its normal level at 24 h. The 24 h recovery process was triphasic and biphasic respectively after EMP exposure at 100 kV/m and 400 kV/m. Following exposure to 400 kV/m EMP, the HRP permeability increased at 112 h and returned to its normal level at 24 h. Western blotting showed that the claudin5 and ZO1 protein levels were changed after EMP exposure. Conclusion EMP exposure at 100 kV/m and 400 kV/m can increase the permeability of in vitro BBB model and BBB tight junctionrelated proteins such as ZO1 and claudin5 may change EMPinduced BBB permeability.
Findings		Effects
Status		Completed With Publication
Principal Investigator		4th Military Medical University, Xi'an, China
Funding Agency		Nat'l Res Prog, China
Country		CHINA
References		Qiu, LB et al. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi, (2009) 27:539-543 Ding, GR et al. Biomed Environ Sci, (2009) 22:265-268 Zhang, YM et al. Biomed Environ Sci., (2012) 25:197-202 Zhou, JX et al. Biomed Environ Sci., (2013) 26:128-137 Wang, XW et al. Toxicology., (2010) 276:58-63
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