Figure 6

Effect of a single MMP-2/9 inhibitor administration on allodynia and hyperalgesia in naive rats. A single intra-plantar administration of MMP-2/9 inhibitor (MMP-2/9I.; 10, 20, 40 μg, i.pl.) induced mechanical allodynia and thermal hyperalgesia as measured by von Frey and Hargreaves tests. However, the treatment had no effect on cold allodynia as measured by acetone test. Behavior: the von Frey (A), Hargreaves (B) and acetone (C) tests were performed 30, 60, 180 min and 24 h after MMP-2/9 inhibitor administration. Results are presented as the mean ± SEM (n = 6–8 rats/group). Inter-group differences were analyzed by Bonferroni’s multiple comparison test. *p < 0.05, **p < 0.01, ***p < 0.001, compared to vehicle-treated (V) naïve rats.