FIGURE 3.

Effects of luzindole on pain behavior, the melatonin level, and MT1 expression. Showing the effect of luzindole on nociceptive thresholds to thermal stimulation and on the efficacy of taVNS (A), plasma melatonin concentration (B), and the expression of MT1 in amygdala (Day 7; C). D, day; the red arrow, CCI operation; the green up arrow, treatments start; the green down arrow, treatments end (Day 6); the blue arrow, sacrifice; N/V, a naive plus vehicle; N/L, naive plus luzindole; C/E/V, CCI plus a taVNS plus vehicle; C/E/L, CCI plus taVNS plus luzindole. *p < 0.05, as compared with naive or the N/V group on the same day and with the baseline of the same group; #p < 0.05, as compared with N/L and C/E/L groups; and +p < 0.05, as compared with N/L.