Fig. 1
From: Hydrogen attenuates postoperative pain through Trx1/ASK1/MMP9 signaling pathway
MMP-9 plays a crucial role in the development of plantar incision-induced postoperative pain. A Mechanical threshold of mice that received plantar incision surgery (n = 12). B MMP-9 activity was measured using zymography after surgery in the spinal cord of mice (n = 4). C MMP-9 expression in the spinal cord of mice was measured using western blot after surgery (n = 4). Lumbar spines (L4–L5) were collected and analyzed 5 days after surgery. D Mechanical threshold of wild-type or MMP-9 KO mice that underwent plantar incision surgery (n = 6). PI = plantar incision. Significant difference is revealed following two-way ANOVA (A and D) or unpaired Student’s t-test (B, C) (*P < 0.05, **P < 0.01, ***P < 0.001 vs. sham; &P < 0.05, &&P < 0.01 vs. PI group; Bonferroni post hoc tests)