CHARACTER OF THE EFFECT OF MICROWAVE ON CONDUCTION-VELOCITY OF FROG VENTRICULAR MUSCLE

Thirty-two frog hearts were divided into four groups and placed indivi dually in temperature-controlled waveguides filled with Ringer's solut ion. The pacemaker was removed, and stimulation was provided at 0.3 Hz by three carbon-loaded Teflon electrodes located on the aorta and the ventricular muscle. Conduction velocity was measured from the differe nce between two action potentials. One group served as control; the th ree other groups were exposed for 2 h to pulsed 2,450 MHz microwave fi elds (10 mu s, 0.001 duty cycle, 16 Hz modulation) at specific absorpt ion rates (SARs) of 0.003, 2, and 6 W/kg, respectively. No significant difference in conduction velocity was found between the control and t he exposed groups, (C) 1994 Wiley-Liss, Inc.