Fig. 8

Intrathecal delivery of miR-21 antagomir prevents mechanical hypersensitivity and reduces macrophage numbers in the DRG following SNI injury. a Effect of continuous intrathecal delivery of the miR-21-5p antagomir (12 pmol/day) for 7 days on the development of mechanical hypersensitivity. b No effect on contralateral nociceptive thresholds of miR-21-5p, scrambled oligomers, or vehicle. Data are presented as 50% of paw withdrawal thresholds (PWT); means ± S.E.M., n = 6 mice in vehicle group and 12 mice in oligomer-treated groups. *P < 0.05, **P < 0.01, ***P < 0.001 compared to vehicle; ^## P < 0.01, ^### P < 0.001 compared to scrambled oligomer, two-way ANOVA followed by Tukey test. Scrambled oligomer and miR-21-5p antagomir (green) distribution in L5 DRG and co-localization with the neuronal marker β-tubulin (red; c, d, i) macrophage marker F4/80 (red; e, f, i), or the satellite cell marker GFAP (red; g–i). Scale bar = 50 μm. j Macrophage infiltration (F4/80, red) in ipsilateral and contralateral L5 DRG. Scale bar = 50 μm. k Quantification of F4/80⁺ cells in L4 and L5 DRG ipsilateral and contralateral to injury following intrathecal delivery of either the scrambled oligomer or miR-21-5p antagomir. Data are means ± S.E.M., n = 4 for each group. ***P < 0.001, one-way ANOVA, post hoc Bonferroni