Detailed characterization of neuro-immune responses following neuropathic injury in mice (original) (raw)

Partial sciatic nerve injury is a common model of neuropathic pain in rodents, and produces both mechanical and thermal pain hypersensitivity. Several types of immune cells have been implicated in the pathogenesis of neuropathic pain due to nerve injury; however, the timing of their appearance has not been fully elucidated. Here, using immunohistochemistry, we characterized the time course and magnitude of inflammatory cell infiltration and resident immune cell activation in the sciatic nerves, L3-5 dorsal root ganglia (DRGs) and spinal segments following partial ligation of the sciatic nerve (PSNL) in C57BL/6J mice. PSNL markedly decreased paw withdrawal threshold to mechanical stimuli and paw withdrawal latency to thermal stimuli in the injured side. No changes were observed in the uninjured contralateral side. Mechanical allodynia persisted, and thermal hyperalgesia resolved by 2 weeks after injury. We found a significant increase in the numbers of infiltrating neutrophils,