Evidence for a distinct neuro-immune signature in rats that develop behavioural disability after nerve injury

作者：Paul J. Austin, Annika M Berglund, Sherman Siu, Nathan T. Fiore, M. B. Gerke-Duncan, Suzanne L Ollerenshaw, Sarah-Jane Leigh, Priya A Kunjan, James W. M. Kang, K. Keay · 发表于：Journal of Neuroinflammation · 年份：2015 · DOI：10.1186/s12974-015-0318-4 · 被引用次数：56 · 研究领域：Psychology、Medicine

BackgroundChronic neuropathic pain is a neuro-immune disorder, characterised by allodynia, hyperalgesia and spontaneous pain, as well as debilitating affective-motivational disturbances (e.g., reduced social interactions, sleep-wake cycle disruption, anhedonia, and depression). The role of the immune system in altered sensation following nerve injury is well documented. However, its role in the development of affective-motivational disturbances remains largely unknown. Here, we aimed to characterise changes in the immune response at peripheral and spinal sites in a rat model of neuropathic pain and disability.MethodsSixty-two rats underwent sciatic nerve chronic constriction injury (CCI) and were characterised as either Pain and disability, Pain and transient disability or Pain alone on the basis of sensory threshold testing and changes in post-CCI dominance behaviour in resident-intruder interactions. Nerve ultrastructure was assessed and the number of T lymphocytes and macrophages were quantified at the site of injury on day six post-CCI. ATF3 expression was quantified in the dorsal root ganglia (DRG). Using a multiplex assay, eight cytokines were quantified in the sciatic nerve, DRG and spinal cord.ResultsAll CCI rats displayed equal levels of mechanical allodynia, structural nerve damage, and reorganisation. All CCI rats had significant infiltration of macrophages and T lymphocytes to both the injury site and the DRG. Pain and disability rats had significantly greater num...