Fig. 2

BTX-A elevated pain threshold of NP rats through targeting TLR2. SD rats were randomly divided into five groups: Sham, CCI-induced NP, BTX-A (rats were given 20 U/kg of BTX-A following CCI), BTX-A + LV-NC (NP rats were given 20 U/kg of BTX-A and lentivirus carrying NC) and BTX-A + LV-TLR2 (NP rats were given 20 U/kg of BTX-A and lentivirus carrying pcDNA-TLR2). a Threshold of mechanical withdrawal in rats were measured at 0, 3, 5, 7, 9, 11, 13, 15 days after induction of CCI. b Latency of thermal withdrawal in rats also were ensured at 0, 3, 5, 7, 9, 11, 13, 15 days after induction of CCI. Blank arrows indicate the boundary between gray matter and white matter. Yellow arrows indicate the glia cells. c Expression of Iba1 in spinal cord tissues was detected using immunohistochemistry assay. d Concentration of IL-1β, IL-6 and TNF-α were examined using ELISA. e qRT-PCR was performed to detect expression of SNAP23 mRNA. f Western blotting assay was carried out to examine levels of p-SNAP23 and SNAP23 in spinal cord tissues. **P < 0.01 contrasted with Sham group, ^##P < 0.01 contrasted with NP group, and ^$$P < 0.01 compared with BTX-A group