Inter‐beat intervals of cardiac‐cell aggregates during exposure to 2.45 GHz CW, pulsed, and square‐wave‐modulated microwaves

摘要

AbstractInter‐beat intervals of aggregated cardiac cells from chicken embryos were studied during 190 s exposures to 2.45 GHz microwaves in an open‐ended coaxial device. Averaged specific‐absorption rates (SARs) and modulation conditions were 1.2–86.9 W/kg continuous‐wave (CW). 1.2–12.2 W/kg pulse modulation (PW, duty cycle ∽ 11). and 12.0–43.5 W/kg square‐wave modulation (duty cycle = 50). The inter‐beat interval decreased during microwave exposures at 42.0 W/kg and higher when CW or square‐wave modulation was used, which is consistent with established effects of elevated temperatures. However, increases in the inter‐beat interval during CW exposures at 1.2–12.2 W/kg, and decreases in the inter‐beat interval after PW exposures at 8.4–12.2 W/kg. are not consistent with simple thermal effects. Analysis of variance indicated that SAR. modulation, and the modulation‐SAR interaction were all significant factors in altering the interbeat interval. The latter two factors indicated that the cardiac cells were affected by athermal as well as thermal effects of microwave e