Interaction of low level modulated RF radiation with Na+-K+-ATPase

The effect of low-level amplitude modulated radiofrequency radiation were s tudied on Na+-K+-ATPase activity in the brain of developing male Wistar rat s of age 23 days (body weight 55-60 g). They were exposed to carrier wave ( CW) frequency 147 MHz and its sub-harmonic frequencies 73.5 and 36.75 MHz a mplitude modulated (AM) at 16 and 76 Hz for 30-35 days (3 h day(-1), Power density 1.47 mW cm(-2),average specific absorption rate 9.65-6.11 W kg(-1)) . We observed a statistically significant increase in Na+-K+-ATPase activit y in chronically exposed rats compared to the control ones. The increase in Na+-K+-ATPase activity was around 19-20% in the rats exposed to CW frequen cies AM at 16 Hz compared to the controls, whereas the increase in Na+-K+-A TPase activity was around 15-16% in rats exposed to the same set of CW freq uencies but AM at 76 Hz. Though there was a difference in Na+-K+-ATPase act ivities (3-4%) in the two groups but the difference was found to be statist ically insignificant. Within the group of rats exposed to CW frequencies am plitude modulated at 16 and 76 Hz, respectively, the effect on Na+-K+-ATPas e activity was found to be independent of the magnitude of CW frequencies. An additional single short duration (20-60 min) exposure of membranes in vi tro from different exposed group to the above field did not show any signif icant alteration on Na+-K+-ATPase activity. It is concluded that a low leve l effect of amplitude modulated radiation produces statistically significan t effect on Na+-K+-ATPase activity but is insensitive to the carrier wave f requencies under investigation. (C) 1998 Elsevier Science S.A. All rights r eserved.