Animal Models of Neuropathic Pain

Despite its prevalence, nerve injury-related (neuropathic) pain in humans is not well understood and, as such, remains difficult to manage (1 –3 ). A variety of clinical conditions can lead to neuropathic pain, which contributes to our lack of understanding of this phenomenon. Although there is substantial etiological heterogeneity among neuropathic pain conditions, commonalities exist. For example, most patients present with combinations of spontaneous and stimulus-evoked pain, the latter of which is characterized by a hypersensitivity to previously innocuous tactile or thermal stimuli (allodynia). To improve our understanding of neuropathic pain, the challenge for basic scientists has been twofold: 1) to develop animal models of persistent pain that more closely mimic clinical pain in humans; and 2) to ensure high reproducibility, within and between animals, across different investigators and laboratories.