Figure 4

The changes on the tail-flick latency or paw flinches produced by formalin in the rats. (A) Time course of the changes induced by the injection (arrow) of saline (0.10 μL) into the Zusanli acupoint at 5 mm below the skin surface or 1% formalin (0.10 μL) into sites indicated in the inset on the tail-flick latency. (B) Time course of the changes induced by intraplantar injection of 1% or 2.5% formalin (0.10 μL) at time 0 on the cumulative flinches of the rats. (C) Time course of the changes induced by an intraplantar injection of saline (0.10 μL), 1% or 2.5% formalin (0.10 μL) on the tail-flick latency of the rats. Points are means (± SD) of six rats per group. P < 0.05 compared to saline (*) or any other group (#), using the Bonferroni post hoc test.