Figure 1. Time course of the antinociceptive effect of bupivacaine on the vocalization threshold to paw pressure after injection of carrageenin. S PRE = group receiving normal saline 5 min before the injection of carrageenin; S POST = group receiving normal saline 60 min after the injection of carrageenin; BUPI PRE = group receiving bupivacaine 5 min before the injection of carrageenin; BUPI POST = group receiving bupivacaine after the injection of carrageenin. *P < 0.05 BUPI PRE versus BUPI POST. Values are expressed as mean+/-SEM.