ID Number		505
Study Type		In Vivo
Model		900 MHz (GSM), 2450 MHz (CW, AM-16 Hz) exposure to mice /rats and analysis of signaling and tissue Ca++ distribution
Details		In initial studies, rats were exposed to 900 MHz GSM RF at 1mW/cm2 for 1 hour, sacrificed, and analyzed for Ca++ precipitation in the temporal cortex as detected by pyroantimonate precipitatation and microscopy. The authors report an increase in Ca++ precipitation both immediately following as well as 1 hour after exposure, but not 24 hours after exposure. In subsequent studies, CFLP mice (males) were exposed to 2450 MHz (CW & AM at 16 Hz) for 3 hours at 0.33, 0.82, or 1.64 W/kg (whole body average) in the far field using a horn antenna. Mice were analyzed immediately or 1, 3, or 24 hr after exposure. Exposure with AM at 16 Hz (but not CW) 2450 MHz microwaves at the highest levels resulted in a change in distribution of pyroantimonate (Ca++) deposits in the intestine as well as a decrease in CaATPase activity that was reversible with a 24 hour recovery period. In addition, the distribution of Ca++ precipitates and CaATPase activity in synaptic vesicles of the medial habenula was also altered. In other studies in vitro, (Scanning Microsc (1991) 5:1145-1155), mouse embryo 3T3 fiberblasts were exposed as above at SARs of up to 2.4 W/kg and analyzed for morphological changes. Exposure with 2450 MHz AM decreased the amount of free negative charges on cell surface as measured by the binding of cationized ferritin and caused more pronounced ultrastructural alterations. These effects could be seen with CW exposures, but at 10 fold higher SAR levels. The authors concluded that AM microwave exposure produced significantly more morphological changes than CW fields of the same intensity. In another in vitro study, (Scanning Microscopy 5, 1145-1155 and 7: 1255-1261; Acta Neurophathol. (in press), epithelial (HT-29 cells) and neuroblastoma cell culture (in vitro) and rat temporal cortex and habenule (in vivo) were exposed as above at an SAR of 1.41 W/kg. Modulated microwave irradiation (2.45 GHz, 16 Hz AM, 1 mW cm-2) caused changes of cell surface negative charges in cell culture, induced redistribution of pyroantimonate precipitable calcium in HT-29 cells and habenule without changes of Ca-activated ecto-ATPase activity and an elevation in cyclic GMP and cyclic AMP level as well as adenylate cyclase activity were observed in small intestine. Finally, a study is ongoing in human epithelial and neuroblastoma cell lines exposed to 900 MHz (GSM) in a TEM cell at 1 mW/cm2. Following exposure, intracellular Ca++, activity of Ca++ dependent ATPase, and cytoskeletal ultrastructure will be analyzed.
Findings		Effects
Status		Completed With Publication
Principal Investigator		Res. Inst. for Radiobiol & Radiohyg, Hungary - thuroczy@hp.osski.hu
Funding Agency		Ministry of Welfare, Hungary
Country		HUNGARY
References		Kittel, A et al. Acta Neuropathol. (Berl), (1996) 92:362-368 Somosy, Z et al. Scanning Microscopy, (1994) 8:613-620 Somosy, Z et al. Scanning Microscopy, (1991) 5:1145-1155
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