ID Number		582
Study Type		In Vivo
Model		900 MHz (GSM) exposure to adult and neonatal mice and analysis of blood brain barrier permeability
Details		BalbCxCBA mice were exposed to 900 MHz (GSM) in a Ferris Wheel exposure system (far field whole body exposure) and analyzed for blood brain barrier permeability. Areas of analysis included cerebral cortex, thalamus, basal ganglia, hippocampus, cerebellum, midbrain and medulla. In initial studies, the wild-type mice (n = 30, non-transgenics from the PIM-1 Repacholi replication study) were used and exposed for 1 hour at 4 W/kg. Control mice were either sham-exposed (n=10) or permitted free movement in a cage (n=10) to exclude any stress-related effects. Although increased blood brain barrier permeability in a positive control group exposed to clostridia toxin (known to increase vascular permeability in the brain) was observed using albumin immuno-histochemistry, no effects of RF exposure were observed. In a follow-on study using mice exposed for the duration of the associated Repacholi replication / bioassay (104 weeks), BBB was again analyzed. In this study, mice had been exposed in restraining tubes as above at SARS of 0.25, 0.5, 1.0, & 4.0 W/kg (whole body average) for 1 hour/day, 5 days/wk, for 104 weeks. Again, no effect on BBB permeability was observed. Brain tissue samples were apparently saved from the animals used in the PIM-1 follow-up study and analyzed for BBB permeability at a later date. This chronic BBB study also looked at dark neuron staining, apparently prompted by results reported by Salford et al. published in Environmental Health Perspectives (2003). The chronic study could also not repeat the effect reported by Salford et al. on dark neuron staining or BBB permeability. A subsequent series of studies included RF exposure in utero (4 W/kg for 1 h/day on gestation days 1-19) as well as neonatally (7 days after birth) and again reported no effects of RF exposure on BBB permeability. In a subsequent study, the water channel protein aquaporin-4 (AQP-4) was evaluated in the exposed mouse brains as an indicator of increasing fluid in the brain tissue, and the authors found no increased expression of AQP-4.
Findings		No Effects
Status		Completed With Publication
Principal Investigator		Inst. of Med. and Vet. Sci., Australia - tim.kuchel@imvs.sa.gov.au
Funding Agency		NHMRC, Australia
Country		AUSTRALIA
References		Finnie, JW et al. Pathology., (2006) 38:63-65 Finnie, J et al. Pathology., (2006) 38:262-263 Finnie , JW et al. Pathology, (2004) 36:96-97 Finnie, JW et al. Pathology, (2002) 34:344-347 Finnie, JW et al. Pathology, (2001) 33:338-340
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