Detection of pain and stress by monitoring gene expression

One of the main concerns with regard to animal experimentation is that if animals must be used for experimental purposes, pain and distress should be abolished or reduced to an absolute minimum. Regarding the principles of the 3Rs, considerable progress has been made concerning reduction and replacement, however to implement refinement it is necessary to improve our ability to objectively recognise signs of pain and distress. Here we present preliminary results indicating that gene expression analysis with DNA microarrays results in characteristic molecular signatures, which allow the identification of different pain and stress levels in mice.