Figure 6
From: Optogenetic activation of brainstem serotonergic neurons induces persistent pain sensitization
Repeated optical stimulation in the RVM of TPH2-ChR2 mice induces long-lasting behaviors of pain sensitization. (A and B) Changes in sensitivity of mechanical pain (A) and thermal pain (B) before (baseline) and after repeated light stimulation (arrows) given for 5 min once daily for 3 days on day 0 through day 2 in WT (n =6) and TPH2-ChR2 mice (n =7). Pain tests were performed once daily. (C) Schematic drawing of brain slices illustrating tip positions of the optical cannulas (circle, WT; triangle, TPH2-ChR2). Numbers on the right are distance from Bregma. * p <0.05, ** p <0.01, *** p <0.001 (two-way ANOVA and Bonferroni’s post hoc analysis).