title: No Dynamic Changes in Blood-brain Barrier Permeability Occur in Developing Rats During Local Cortex Exposure to Microwaves.
abstract: Little information is available about the effects of exposure to radiofrequency electromagnetic fields (RF) on cerebral microcirculation during rat developmental stages. We investigated whether the permeability of the blood-brain barrier (BBB) in juvenile and young adult rats was modified during local cortex exposure to RF under non-thermal conditions. The cortex tissue targeted was locally exposed to 1457 MHz RF at an average specific absorption rate of 2.0 W/kg in the target area for 50 min and permeability changes in the BBB of the pia mater were measured directly, using intravital fluorescence microscopy. There was no significant difference in extravasation of intravenously-injected dye between exposed and sham-exposed groups of either category of rats. No histological evidence of albumin leakage was found in any of the brains just after exposure, indicating that no traces of BBB disruption remained. These findings suggest that no dynamic changes occurred in BBB permeability of the rats at either of these developmental stages, even during local RF exposure at non-thermal levels.
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan Department of Environmental Health, National Institute of Public Health, Saitama, Japan bdxmsd@yahoo.co.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Masuda
authors.affiliation: Department of Environmental Health, National Institute of Public Health, Saitama, Japan.
authors.forename: Shogo
authors.initials: S
authors.lastname: Hirota
authors.affiliation: Department of Environmental Health, National Institute of Public Health, Saitama, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ushiyama
authors.affiliation: Department of Computer Science and Engineering, Nagoya Institute of Technology, Aichi, Japan.
authors.forename: Akimasa
authors.initials: A
authors.lastname: Hirata
authors.affiliation: Department of Electrical and Electronics Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Arima
authors.affiliation: Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Tokyo, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kawai
authors.affiliation: Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Tokyo, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Wake
authors.affiliation: Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Tokyo, Japan.
authors.forename: Soichi
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Department of Electrical and Electronic Engineering, Tokyo Metropolitan University, Tokyo, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Taki
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Nagai
authors.affiliation: Japan EMF Information Center, Tokyo, Japan.
authors.forename: Chiyoji
authors.initials: C
authors.lastname: Ohkubo
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism* / Q000528:radiation effects; D002199:Capillary Permeability / Q000528:radiation effects*; D003911:Dextrans / Q000493:pharmacokinetics; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D008297:Male; D008872:Microwaves; D017207:Rats, Sprague-Dawley
chemical_list: D003911:Dextrans; D005456:Fluorescent Dyes; C015219:fluorescein isothiocyanate dextran; D016650:Fluorescein-5-isothiocyanate
keywords: Radiofrequency electromagnetic field; blood-brain barrier; development stage; juvenile; local exposure; temperature; young adult