Fig. 2.

Focal knockdown of spinal CARM1 expression elicits no motor deficits but provokes behavioral allodynia. (a) Diagram of the timeline of this experiment. (b) Representative Western blot and statistical analysis (normalized to GAPDH) demonstrating that intrathecal administration of CARM1 siRNA (CARM1 siRNA; 100 ng; 10 μL; once daily for 4 days) but not missense siRNA (MS siRNA, 100 ng, 10 μL) or polyethylenimine (PEI, a transfection reagent, 10 μL) led to decrease in CARM1 levels in the dorsal horn of naïve rats at day 4 after injection. IB, Immunoblotting. **p < 0.01 versus Naïve. ^##p < 0.01 versus MS siRNA. Each group has 5 rats. One-way ANOVA, F_{(3, 16)} = 15.35, p < 0.0001. (c) Representative Western blot and statistical analysis (normalized to GAPDH) demonstrating that intrathecal administration of CARM1 siRNA (100 ng; 10 μL; once daily for 4 days) did not decrease in PRMT6 levels in the dorsal horn of naïve rats at day 4 after injection. Each group has 5 rats. One-way ANOVA, F_{(3, 16)} = 0.2426, p = 0.8654. (d) Rota-rod test demonstrating no statistical difference in the motor performance among Naïve, PEI, MS siRNA, and CAM1 siRNA groups (100 ng; 10 μL; once daily for 4 days). The gray bar at the bottom indicates the duration of the reagents’ intrathecal administration. Each group has 6 rats. Two-way ANOVA, group, F_{(3, 20)} = 1.842, p = 0.1720; time, F_{(4, 80)} = 1.222, p = 0.3082; interaction, F_{(12, 80)} = 0.9595, p = 0.4939. (e) Results of the von Frey test demonstrating that administering naïve rats with CARM1 siRNA (100 ng; 10 μL; once daily for 4 days) decreased the withdrawal threshold of the hind paw at days 1, 2, 3, and 4 after the injection. The gray bar at the bottom indicates the duration of the reagents’ intrathecal administration. *p < 0.05, **p < 0.01 versus Naïve. ^##p < 0.01 versus MS siRNA. Each group has 6 rats. Two-way ANOVA, group, F_{(3, 20)} = 32.47, p < 0.0001; time, F_{(4, 80)} = 5.394, p = 0.0007; interaction, F_{(12, 80)} = 4.405, p < 0.0001