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Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy.

Publication ,  Journal Article
Hwang, PY; Allen, KD; Shamji, MF; Jing, L; Mata, BA; Gabr, MA; Huebner, JL; Kraus, VB; Richardson, WJ; Setton, LA
Published in: Open Orthop J
2012

Intervertebral disc herniation may contribute to inflammatory processes that associate with radicular pain and motor deficits. Molecular changes at the affected dorsal root ganglion (DRG), spinal cord, and even midbrain, have been documented in rat models of radiculopathy or nerve injury. The objective of this study was to evaluate gait and the expression of key pain receptors in the midbrain in a rodent model of radiculopathy. Radiculopathy was induced by harvesting tail nucleus pulposus (NP) and placing upon the right L5 DRG in rats (NP-treated, n=12). Tail NP was discarded in sham-operated animals (n=12). Mechanical allodynia, weight-bearing, and gait were evaluated in all animals over time. At 1 and 4 weeks after surgery, astrocyte and microglial activation was tested in DRG sections. Midbrain sections were similarly evaluated for immunoreactivity to serotonin (5HT(2B)), mu-opioid (µ-OR), and metabotropic glutamate (mGluR4 and 5) receptor antibodies. NP-treated animals placed less weight on the affected limb 1 week after surgery and experienced mechanical hypersensitivity over the duration of the study. Astroctye activation was observed at DRGs only at 4 weeks after surgery. Findings for pain receptors in the midbrain of NP-treated rats included an increased expression of 5HT(2B) at 1, but not 4 weeks; increased expression of µ-OR and mGluR5 at 1 and 4 weeks (periaqueductal gray region only); and no changes in expression of mGluR4 at any point in this study. These observations provide support for the hypothesis that the midbrain responds to DRG injury with a transient change in receptors regulating pain responses.

Duke Scholars

Published In

Open Orthop J

DOI

EISSN

1874-3250

Publication Date

2012

Volume

6

Start / End Page

383 / 391

Location

United Arab Emirates
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Hwang, P. Y., Allen, K. D., Shamji, M. F., Jing, L., Mata, B. A., Gabr, M. A., … Setton, L. A. (2012). Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy. Open Orthop J, 6, 383–391. https://doi.org/10.2174/1874325001206010383
Hwang, Priscilla Y., Kyle D. Allen, Mohammed F. Shamji, Liufang Jing, Brian A. Mata, Mostafa A. Gabr, Janet L. Huebner, Virginia B. Kraus, William J. Richardson, and Lori A. Setton. “Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy.Open Orthop J 6 (2012): 383–91. https://doi.org/10.2174/1874325001206010383.
Hwang PY, Allen KD, Shamji MF, Jing L, Mata BA, Gabr MA, et al. Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy. Open Orthop J. 2012;6:383–91.
Hwang, Priscilla Y., et al. “Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy.Open Orthop J, vol. 6, 2012, pp. 383–91. Pubmed, doi:10.2174/1874325001206010383.
Hwang PY, Allen KD, Shamji MF, Jing L, Mata BA, Gabr MA, Huebner JL, Kraus VB, Richardson WJ, Setton LA. Changes in midbrain pain receptor expression, gait and behavioral sensitivity in a rat model of radiculopathy. Open Orthop J. 2012;6:383–391.

Published In

Open Orthop J

DOI

EISSN

1874-3250

Publication Date

2012

Volume

6

Start / End Page

383 / 391

Location

United Arab Emirates