TRPV1 and neuropathy, small fiber: Taken together with our previous study (Wu et al., 2016), these results suggest that microdomains on sensory neurons act as functional units for pain transduction in two stages: (1) in the acute stages of small-fiber neuropathy, disruption of microdomains containing TRPV1 and adenosine signaling molecules prevents pain transmission and (2) in the chronic stages, the degree of neuronal injury is the critical factor for pain hypersensitivity in addition to the molecular interaction within microdomains (Fig. 8).