Skin/Muscle Incision and Retraction Induces Evoked and Spontaneous Pain in Mice

Figure 3

Systemic administration of clonidine raised the paw withdrawal threshold (PWT) in skin/muscle incision and retraction (SMIR) mice. (a) Saline had no effect on the PWTs in the sham and SMIR groups injected at day 4 after SMIR (two-way RM ANOVA, sham versus SMIR: F1; 17 = 35.83, ; treatments: F1; 17 = 0.55, , interaction: F1; 17 = 1.74, ; n = 7 for the sham group, n = 8 for the SMIR group, under Sidak’s multiple comparisons test). (b) SMIR decreased the PWTs, which was not changed by the application of clonidine at 0.02 mg/kg (two-way RM ANOVA, sham versus SMIR: F1; 17 = 87.23, ; treatments: F1; 17 = 0.08, , interaction: F1; 17 = 0.33, ; n = 9 for the sham group, n = 10 for the SMIR group, under Sidak’s multiple comparisons test). (c) Clonidine at 0.1 mg/kg increased the PWTs of the SMIR group (two-way RM ANOVA, sham versus SMIR: F1; 17 = 24.07, ; treatments: F1; 17 = 37.01, , interaction: F1; 17 = 26.54, ; n = 9 for the sham group, n = 10 for the SMIR group, under Sidak’s multiple comparisons test). (d) Clonidine at 0.5 mg/kg increased the PWTs of both the SMIR group and the sham group (two-way RM ANOVA, sham versus SMIR: F1; 17 = 24.04, ; treatments: F1; 17 = 273.3, , interaction: F1; 17 = 19.53, ; n = 9 for the sham group, n = 10 for the SMIR group, under Sidak’s multiple comparisons test). ANOVA, analysis of variance; RM, repeated measures.

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