Fig. 2: Knockdown of spinal Munc13-1 expression relieves SNL-induced allodynia.

a Representative Western blot and statistical analysis (normalized to GAPDH) demonstrating that the intrathecal administration of Munc13-1 siRNA (Munc13-1 siRNA; 1, 3, and 5 μg; 10 μL; once daily for 4 days), but not missense siRNA (MS siRNA, 3 μg, 10 μL) or polyethylenimine (a transfection reagent, PEI, 10 μL), dose-dependently decreased spinal Munc13-1 expression in naive rats. it, implantation of an intrathecal catheter. IB immunoblotting. **P < 0.01 compared with naive (n = 6). b Intrathecal application of neither Munc13-1 siRNA (Munc13-1 siRNAi, 3 μg, 10 μL) nor missense siRNA (MS siRNA, 3 μg, 10 μL) resulted in motor deficits in rats (Rotarod test). The gray bar at the bottom indicates the duration of intrathecal administration (n = 7). c Intrathecal Munc13-1 siRNA (SNL 7D + it + Munc13-1 siRNA; 3 μg, 10 μL) increased the withdrawal threshold of SNL animals on post-operative days 5 and 7 (von Frey test). The gray bar at the bottom indicates the duration of intrathecal administration. **P < 0.01 compared with SNL (n = 7). d, e Representative Western blot and statistical analysis (normalized to GAPDH and N-Cad, respectively) demonstrating that Munc13-1 siRNA (SNL 7D + Munc13-1 siRNA; 3 μg, 10 μL; once daily at days 3–6 after SNL) decreased the Munc13-1 expression in the total homogenate and synaptic plasma membranes (SPM) of the ipsilateral dorsal horn on post-SNL day 7. IB immunoblotting, SPM IB synaptic plasma membranes immunoblotting. **P < 0.01 compared with SNL 7D (n = 6). f Treatment of Munc13-1 siRNA (SNL 7D + it + Munc13-1 siRNA; 3 μg, 10 μL; once daily at days 3–6 after SNL) ameliorated the SNL-induced mechanical allodynia from days 5 to 17 after injury. *P < 0.05, **P < 0.01 vs. SNL n = 7. Results were expressed as mean ± SEM