Figures & data
Figure 1 Effect of topically applied mepivacaine on mechanical hyperalgesia in rats with gp120-induced neuropathic pain.
Notes: (A) Effects of several concentrations (in millimolars) of topical mepivacaine or vehicle on hind paw withdrawal thresholds (in grams). Withdrawal thresholds before application of gp120 to the sciatic nerve (“pre-gp120”) and 2 weeks after, prior to topical application (“predrug”), were measured. Rats were tested within 1 minute (“immediate”) of removal of the gauze pad, and 5 and 10 minutes following removal of the gauze pad. Data are presented as mean ± standard error of the mean (n=7–10 animals per treatment group). (B) Percent changes in mechanical withdrawal thresholds following topical mepivacaine treatment, calculated from predrug baseline scores in (A). (C) Percent of animals in each concentration group reaching ≥33% increase in mechanical withdrawal threshold from predrug baselines. *P<0.05, **P<0.01, and ***P<0.001 vs vehicle-treated rats.
Figure 2 Effect of topically applied mepivacaine on thermal hyperalgesia in rats with gp120-induced neuropathic pain.
Notes: (A) Effects of several concentrations (in millimolars) of topical mepivacaine or vehicle on hind paw withdrawal latencies (in seconds). Withdrawal latencies before application of gp120 to the sciatic nerve (“pre-gp120”) and 2 weeks after, prior to topical application (“predrug”), were measured. Rats were tested within 1 minute (“immediate”) of removal of the gauze pad, and 5 and 10 minutes following removal of the gauze pad. Data are presented as mean ± standard error of the mean (n=7–10 animals per treatment group). (B) Percent changes in thermal withdrawal latencies following topical mepivacaine treatment, calculated from predrug baseline scores in (A). (C) Percent of animals in each dose group reaching ≥33% increase in thermal withdrawal latencies from predrug baselines. *P<0.05, **P<0.01, and ***P<0.001 vs vehicle-treated rats.
Figure 3 Effect of topically applied lidocaine on mechanical hyperalgesia in rats with gp120-induced neuropathic pain.
Notes: (A) Effects of several concentrations (in millimolars) of topical lidocaine or vehicle on hind paw withdrawal thresholds (in grams). Withdrawal thresholds before application of gp120 to the sciatic nerve (“pre-gp120”) and 2 weeks after, prior to topical application (“predrug”), were measured. Rats were tested within 1 minute (“immediate”) of removal of the gauze pad, and 5 and 10 minutes following removal of the gauze pad. Data are presented as mean ± standard error of the mean (n=7–10 animals per treatment group). (B) Percent changes in mechanical withdrawal thresholds following topical lidocaine treatment, calculated from predrug baseline scores in (A). (C) Percent of animals in each dose group reaching ≥33% increase in mechanical withdrawal threshold from predrug baselines. *P<0.05, vs vehicle-treated rats.
Figure 4 Effect of topically applied lidocaine on thermal hyperalgesia in rats with gp120-induced neuropathic pain.
Notes: (A) Effects of several concentrations (in miilimolars) of topical lidocaine or vehicle on hind paw withdrawal latencies (in seconds). Withdrawal latencies before application of gp120 to the sciatic nerve (“pre-gp120”) and 2 weeks after, prior to topical application (“predrug”), were measured. Rats were tested within 1 minute (“immediate”) of removal of the gauze pad, and 5 and 10 minutes following removal of the gauze pad. Data are presented as mean ± standard error of the mean (n=7–10 animals per treatment group). (B) Percent changes in thermal withdrawal latencies following topical lidocaine treatment, calculated from predrug baseline scores in (A). (C) Percent of animals in each dose group reaching ≥33% increase in thermal withdrawal latencies from predrug baselines. Asterisks indicate differences between lidocaine treatment compared with saline-treated rats: *P<0.05.
Figure 5 Effects of topically applied mepivacaine and lidocaine on acute nociception in the mouse tail flick assay.
Notes: (A) Effects of several concentrations (in millimolars) of topical mepivacaine, lidocaine, or vehicle on tail flick withdrawal latencies (in seconds). Withdrawal latencies were measured before application of drug to the tail (“baseline”). Mice were tested within 1 minute (“immediate”) of removal of the tail from the topical solution, and 5 and 10 minutes following removal of the tail from the topical solution. Data are presented as mean ± standard error of the mean (n=7–10 animals per treatment group). (B) Percent changes in tail flick latencies following topical anesthetic treatment, calculated from predrug baseline scores in (A). (C) Percent of animals in each dose group reaching ≥33% increase in tail flick latencies from predrug baselines. *P<0.05, **P<0.01 vs vehicle-treated mice.
