Radiofrequency Radiation Effects on Excitable Tissues
Final rept. 1 Jun 1981-30 Oct 1982
GEORGIA INST OF TECH ATLANTA ENGINEERING EXPERIMENT STATION
Pagination or Media Count:
Spheroidal aggregates of cultured chick cardiac cells were used to study effects of 2450-MHz radiofrequency radiation RFR on excitable membranes. Membrane voltage noise was recorded simultaneously with two microelectrodes. Preparation bulk temperature ws 37 or - 0.2 C, and temperature at the aggregate was less than 0.9 C above this during RFR exposures of 2- and 3-min durations. Specific absorption rate SAR was between 1 and 231 mWg, and both continuous-wave CW and pulse-modulated PW, 5 mcirosec at 100 pps RFR were applied using an open-ended coaxial exposure device. Membrane voltage fluctuations, in the form of noise and microspike event and membrane impedance were observed before, during, and after RFR exposures. No RFR effect was seen on membrane impedance viewed as parallel resistance and capacitance. The relation of membrane voltage noise power 0.1-1.0 Hz to membrane potential was significantly altered during the first half of 3-min exposures to 1-5 and 15-30 mWg CW RFR. This was found by using two-tailed t-tests to test the difference in slopes between least-squares linear regression fits of data from different RFR conditions with the significance level set at P0.05. Although microspikes seemed to contribute to this RFR effect on noise, there was no significant difference two-tailed t-test, P0.05 in frequency of occurrence of microspikes greater than 0.2 mV for any RFR exposure condition.