Friedman J, Kraus S, Hauptman Y, Schiff Y, et al. (2007)
The authors investigated the immediate effect of irradiation on
the mitogen-activated protein kinase (MAPK) cascades, which are
involved in transcription and protein stability in cells. They
subjected rat or HeLa cells to RFR at cell phone frequencies (800-900
MHz) with an intensity of 0.07 mW/cm² or higher. This lower
level is well below the average intensity of a cell phone, which
is 0.45 mW/cm² in Israel, where the researchers work. The
temperature of the experiment was controlled to normal levels.
They found that extracellular-signal-regulated kinase (ERK) were
rapidly activated (within seconds) in response to various frequencies
and intensities. This results from an initial mediating step by
NADH oxidase, which rapidly generates reactive oxygen species (ROS).
These in turn activate the ERK cascade, which are one of the MAPK
cascades, and can regulate a variety of physiological responses
in cells and organisms