Pain responses in the formalin test when acupuncture began immediately after pain induction. Pain responses of phase 1 and phase 2 were presented in (A) and total pain response was presented in (B). Sequential pain response was presented in (C). The black bar labeled "Acupuncture" indicates the 5 minute time interval during which the 3 minute treatment occurred for all mice. All data are presented as mean ± SE. No significant difference was found in pain responses compared to the control group.