ID Number		611
Study Type		In Vivo
Model		700 MHz (CW) exposure to rats and analysis of brain cholinergic signaling
Details		Sprague Dawley rats were exposed to 700 MHz (CW) RF at SARs of ~ 20 W/kg for 5 to 15 minutes (until colonic temperature was elevated by 2.5 C). Analysis of the brain showed a consistent change in adrenergic and muscarinic cholinergic receptors in the hypothalamus both during and after exposure. The authors interpret these changes as consistent with the proposed hypothalamic thermoregulatory mechanism. Various studies looking at rat brain synaptosomes or cell cultures exposed to RF. In the 1989 study, rat brain synaptosomes were exposed to 2.8 GHz (PW - 1 usec pulse width, 350 pulses/sec) microwaves at 1, 10, and 30 W/kg using a horn antenna. Exposure at 10 and 30 W/kg resulted in increased uptake of 32P into PIP, PIP2, PI, and PA, but did not change total concentrations of these metabolites suggesting that phosphoinositide turnover was stimulated. Competition studies with lithium, A23187 (Ca++ ionophor), and EGTA indicated a specific pool of inositol phospholipids in the synaptosomal membranes being acted upon by microwaves. The authors suggest these data indicate microwave exposure may affect transmembrane signaling in nerve endings.
Findings		Effects (only at thermal levels)
Status		Completed With Publication
Principal Investigator		University of Texas, San Antonio TX, USA
Funding Agency		Private/Instit.
Country		UNITED STATES
References		Gandhi, VC et al. Radiat. Res., (1997) 109:90-99 Gandhi, CR et al. Radiat. Environ. Biophys., (1989) 28:223-234
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