Figure 2.

Baseline mechanical thresholds (all drug groups combined) of Young-Young (n = 34), Young-Old (n = 25), and Old-Old (n = 33) conditions. Old-Old mice were tested both while “young,” at 18 weeks (wks.) of age, and again at 12 months (mo.) of age. Bars represent mean ± SEM 50% withdrawal threshold (g) to the application of von Frey filaments; both hind paws are averaged. ***P < 0.001 (by ANOVA followed by Tukey's post hoc test; ns, not significantly different (by repeated-measures ANOVA). ANOVA, analysis of variance.