Fig. 5

Time course of joint mechanosensitivity induced by intra-articular injection of MIA (0.3 mg/10 μl) or saline (10 μl) and involvement of PAR2. a In wild-type mice, MIA induced a significant reduction in tolerance to tactile stimuli that was not seen with an intra-articular saline injection (P < 0.0001, two-way ANOVA). b MIA induced mechanical sensitivity in PAR2 knockout (PAR2^−/−) mice (P < 0.001, two-way ANOVA) that was less intense than in wild-type mice. a, b There were no differences in response to saline injection between the wild-type and PAR2 knockout mice (P = 0.61, two-way ANOVA); however, a significant difference was observed between wild-type and PAR2 knockout mice injected with MIA (P < 0.0001, two-way ANOVA) (n = 5–10 per group). *P < 0.05, ****P < 0.0001 as compared with baseline, one-way ANOVA