A comparison of pain-related behavior following local application of nucleus pulposus and/or mechanical compression on the dorsal root ganglion.

Abstract

Symptomatic induction of disc herniation involves both mechanical compression and chemical factors. Inhibitors of tumor necrosis factor-alpha (TNF-α) are known to reduce pain-related behavior in experimental models. Animals were divided into mechanical compression (MC) group; a stainless steel rod was inserted on the dorsal root ganglion, nucleus pulposus (NP) group: NP was harvested from the coccygeal vertebral disc, MC and NP group; rats were received stainless rod and NP, and sham group; rats were received neither rod nor NP. Rats in the MC group received a TNF-α antibody (10 mg/kg) (antibody group) or were not treatment (untreated group). The withdrawal thresholds of the MC, NP and MC+NP groups decreased significantly compared with the sham group. In the antibody group, the threshold was significantly higher than that of the untreated group. An anti-TNF-α antibody reduced allodynia caused by DRG compression.