Faculty Collaboration Database

Mechanical sensitization of cutaneous sensory fibers in the spared nerve injury mouse model. Mol Pain 2013 Nov 29;9:61

Date

11/30/2013

Pubmed ID

24286165

Pubmed Central ID

PMC3906996

DOI

10.1186/1744-8069-9-61

Scopus ID

2-s2.0-84888258179 (requires institutional sign-in at Scopus site)   49 Citations

Abstract

BACKGROUND: The spared nerve injury (SNI) model of neuropathic pain produces robust and reproducible behavioral mechanical hypersensitivity. Although this rodent model of neuropathic pain has been well established and widely used, peripheral mechanisms underlying this phenotype remain incompletely understood. Here we investigated the role of cutaneous sensory fibers in the maintenance of mechanical hyperalgesia in mice post-SNI.

FINDINGS: SNI produced robust, long-lasting behavioral mechanical hypersensitivity compared to sham and naïve controls beginning by post-operative day (POD) 1 and continuing through at least POD 180. We performed teased fiber recordings on single cutaneous fibers from the spared sural nerve using ex vivo skin-nerve preparations. Recordings were made between POD 16-42 after SNI or sham surgery. Aδ-mechanoreceptors (AM) and C fibers, many of which are nociceptors, from SNI mice fired significantly more action potentials in response to suprathreshold mechanical stimulation than did fibers from either sham or naïve control mice. However, there was no increase in spontaneous activity.

CONCLUSIONS: To our knowledge, this is the first study evaluating the contribution of primary afferent fibers in the SNI model. These data suggest that enhanced suprathreshold firing in AM and C fibers may play a role in the marked, persistent mechanical hypersensitivity observed in this model. These results may provide insight into mechanisms underlying neuropathic pain in humans.

Author List

Smith AK, O'Hara CL, Stucky CL

Author

Cheryl L. Stucky PhD Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Hyperalgesia
Male
Mechanotransduction, Cellular
Mice
Mice, Inbred C57BL
Nerve Fibers, Myelinated
Nerve Fibers, Unmyelinated
Nociceptors
Sensory Receptor Cells