Background: Neuropathic pain is a frequent chronic presentation in autoimmune diseases of the nervous system, such as multiple sclerosis
(MS) and Guillain-Barre syndrome (GBS), causing significant individual
disablement and suffering. Animal models of experimental autoimmune
encephalomyelitis (EAE) and experimental autoimmune neuritis (EAN) mimic
many aspects of MS and GBS, respectively, and are well suited to study
the pathophysiology of these autoimmune diseases. However, while much
attention has been devoted to curative options, research into
neuropathic pain mechanisms and relief has been somewhat lacking.
Interpretation: Recent
studies have demonstrated a variety of sensory abnormalities in
different EAE and EAN models, which enable investigations of behavioural
changes, underlying mechanisms, and potential pharmacotherapies for
neuropathic pain associated with these diseases.
Conclusions: This review examines
the symptoms, mechanisms, and clinical therapeutic options in these
conditions and highlights the value of EAE and EAN animal models for the
study of neuropathic pain in MS and GBS.
It is a question on whether you can use these models to look at pain, we too have asked the question. This is a worthy question and something that it would be good to know, but is a disease of a few days going to tell us about the pain evolving over many years...the former you can probably treat with an opioid and paracetamol the later as many people know is a problem to deal with.
Animals show an altered sensory response before disease develops and EAE attacks the sensory tracts in the dorsal horn of the spinal cord so their sensation will get messed up. They show allodynia a withdrawal response away from something that was not considered painful before EAE, during paralytic disease they are anaesthetic and do not feel. What happens after is debatable.......however once people start investigating and reporting pain then this adds an additional level of complexity to the ethics of doing these experiments and will add a further nail in the coffin in many places..........so to the pain modellers reading this, it is best to ensure that the experiments are well designed and meaningful (This is not acute EAE!) and translatable.
I do think there are systems/models where this can be examined but having spent £10,000 or standard measuring devices that have so far proved useless maybe is time to get back in the lab to look for "pain faces".