Fig. 3. The influence of anesthetic type on mechanical withdrawal threshold after hind paw incision. Mechanical threshold was assessed with an electric von Frey device, as described in Materials and Methods. Three days after the induction of persistent inflammation and ∼12 h after an incision in the same hind paw and a 3-h period of anesthesia, there was a significant difference between groups (P = 0.03, one-way ANOVA), where post hoc analysis (Holm-Sidak) indicated that the difference between the pentobarbital (Pento)- and isoflurane (Iso)-anesthetized groups was significantly different (P = 0.02). The ketamine/xylazine (Ket/Xyl)-anesthetized group was not statistically different from the other two (*P > 0.05) (A ). In the absence of persistent inflammation, there was no detectable influence of anesthetic type on mechanical threshold (P > 0.05, one-way ANOVA). Data from the hind paw ipsilateral to the site of incision are plotted as mean ± SEM. Numbers in parentheses are the number of rats in each group (B ).