To test whether a cholinergic neurotransmitter system would be responsive to the exposure conditions that induce calcium-ion flux and to determine whether the response would be windowed or would follow the more classical dose-response kinetics.
Acetylcholinesterase (AChE) as biochemical marker was used because of its presence in the cell membrane and its physiologically important role in the acetylcholinergic neurotransmitter system of intercellular communication.
|Exposure duration||continuous for 30 min|
|Chamber||A transmission-line exposure system was housed in a large incubator maintained at 37°C, as described by Dutta et al. .|
|Setup||Two tissue culture flasks of 25 cm² growth surface containing cells in 5 ml of growth medium were exposed per trial.|
|Additional info||Two control flasks were placed in the incubator outside the transmission line.|
|SAR||0.1 W/kg||-||-||-||0.001, 0.005, 0.01, 0.02, 0.05, or 0.10 W/kg|
The results indicate that exposure to modulated radiofrequency fields at different SARs affects AChE activity of neuroblastoma cells. Enhanced activity was observed within a time window between 7.0 and 7.5 h after the cells were plated and only when the radiation occured at power densities identified in a previous report (publication 232) as being effective for altering the release of calcium ions. Radiofrequency was not effective in changing AChE activity at earlier time points, e.g. 1 and 2 h after plating (data not shown). Thus radiofrequency radiation under these conditions affects both calcium-ion release and AChE activity in a common dose-dependent manner.