Fig. 9.

Blocakade of Sig-1R attenuates SNI-induced pain responses whereas Sig-1R agonist elicits hyperalgesic responses in naive animals. a (+)-Pentazocine produces hypersensitivity in naïve rats. Sig-1R agonist (+)-pentazocine ((+)PTZ)) decreases mechanical withdrawal threshold and increases response rates to mechanical and cold stimuli in naive rats. Detailed information of animal, surgery procedure, and sensory tests are described in the Methods. b BD1047 attenuates hyperalgesic responses in SNI rats. The sensory tests of threshold mechanical stimulation (von Frey filaments), noxious stimulation (pin), soft touch (brush), and cold chemical stimulation (acetone drop) following intraganglionic injection of Sig-1R antagonist (BD1047, 4 μg/2 μl) in SNI rats were evaluated in the plantar skin of the paw ipsilateral with the injected DRG. BD-1047 reduces mechanical and thermal hypersensitivity. Data are means ± SEM; n = 4 in each group except (+)PTZ-injected naïve rat group (n = 6); two-way ANOVA followed by Tukey’s test, *P < 0.05, **P < 0.01