ID Number		1816
Study Type		In Vivo
Model		35 GHz exposure to rats and ananlysis of histopathology and gene expression in teh skin
Details		Sprague Dawley rats were exposed (from the side) to 35 GHz mm waves at 75 mW/cm2 for 24 hours (levels sufficient for a ~+4.5 degree C and ~+2.5 degree C increase in skin and core temperature, respectively) and evaluated for gene expression profiles on Affymatrix chips. The peak temperature on the skin (from infrared thermography) was 41.4 degrees C and in the colon was ~42 degrees C. As a positive control the authors used 42 degree warm air exposure. The authors report pathological findings in the exposed skin of neutrophil aggregation in vessels, degeneration of stromal cells, and breakdown of collagen. They also reported expression changes in 56 (43 up, 13 down regulated) and 58 (27 up and 31 down regulated) genes at 6 and 24 hours of exposure, respectively. These genes were involved in transcription regulation, protein folding, oxidative stress, immune response, and tissue matrix turnover.
Findings		Effects (only at thermal levels)
Status		Completed With Publication
Principal Investigator		Brooks Air Force Base, San Antonio TX, USA - ctr@brooks.af.mil
Funding Agency		AF, USA
Country		UNITED STATES
References		Millenbaugh, NJ et al. Radiation Research, (2008) 169:288-300
Comments		Did not assess the threshold of heat stress, just the effects at known thermal stress. The exposure was known to cause significant heat stress: Millenbaugh NJ, Kiel JL, Ryan KL, Blystone RV, Hurt WD, Ziriax JM, Mason PA. (2006) Comparison of blood pressure and thermal responses in rats exposed to millimeter wave energy or environmental stress. Shock (2006) 25:625-632); Frei MR, Ryan KL, Berger RE, Jauchem JR. Sustained 35 GHz Radiofrequency Irradiation Induces Circulatory Failure. Shock (1995) 4:289-293