Fig. 2. Moxonidine dose-dependently attenuated mechanical hyperalgesia. (A ) Ipsilateral (injured) paw. Moxonidine at 1-nmol (squares) and 0.1-nmol (circles) doses significantly attenuated mechanical hyperalgesia for 90 and 10 min, respectively, whereas 0.03 nmol (triangles) moxonidine moderately decreased hyperalgesia. (B ) Contralateral paw. Moxonidine at 1-nmol (squares) and 0.1-nmol (circles) doses significantly attenuated the hyperalgesia for 60 and 10 min, respectively, whereas 0.03 nmol (triangles) moxonidine moderately decreased hyperalgesia. For both (A ) and (B ) statistical significance of the dose-dependent effect of moxonidine at the 10–60-min time points was shown by repeated-measures analysis of variance followed by Bonferroni post hoc  test. A dose of 0.01 nmol (data not shown) did not have an effect greater than that of acidified saline (diamonds), which had minimal effect on hyperalgesia. Before administration of moxonidine, confirmation of induction of hyperalgesia (similar to that shown in fig. 1) was conducted for this time-course study (data not shown).