ID Number		1452
Study Type		In Vivo
Model		63 MHz (MRI frequency) exposure to rats and analysis of blood brain barrier effects
Details		Rats and mice were exposed to 63 MHz (MRI frequency) for 20 minutes at magnetic field strengths of 0.1  1 T and analyzed for effects on the blood brain barrier (BBB) using 153Gd-DTPA or horseradish peroxidase protein as markers for detection. The authors initially reported exposure at 0.15 T increased BBB permeability, although they acknowledged that other investigators failed to observe similar effects using magnetic field strengths of 1.5 T or higher. When the authors performed studies using higher magnetic field strengths, they again observed BBB permeability increases immediately after exposure that recovered to normal after 15-30 minutes. In other studies, exposure to mice as above was found to attenuate the effects of co-injection with morphine (morphine alone elicits different day- and night-time analgesia responses to a thermal stimulus). The authors suggest magnetic and/or RF field might alter both day- and night-time responses to morphine, and suggest possible alterations in neuronal calcium binding and/or nocturnal pineal gland activity as possible mechanisms.
Findings		Effects
Status		Completed With Publication
Principal Investigator		St. Joseph's Health Centre, London, Ontario, Canad
Funding Agency		Inst. Health Research, Canada
Country		CANADA
References		Prato, FS et al. Microsc Res Tech, (1994) 27:528-534 Prato, FS et al. Ann N Y Acad Sci, (1992) 649:44-58 Prato, FS et al. Brain Research, (1990) 523:301-304 Shivers, RR et al. Neuroscience Letters, (1987) 76:25-31
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