Figure 6. Pharmacological targeting of pruritogenic pathways in urushiol and oxazolone ACD models.

(A) Comparison of scratching behavior in mice after injection of 5-HT₇ receptor antagonist SB269970 (SB), 5-HT_2A receptor antagonist ketanserin (Ket), ET_A receptor antagonist BQ123, H₁ receptor antagonist cetirizine, or TSLP-neutralizing antibody (TSLP Ab) during the first 30 minutes after urushiol challenge. (B) Scratching behavior of the same group of mice as in A, analyzed 4 hours after urushiol challenge. (C) Comparison of scratching behavior in mice after injection of above pharmacological reagents during the first 30 minutes after oxazolone challenge. (D) Scratching behavior of the same group of mice as in C, analyzed 4 hours after oxazolone challenge. Scratching bouts were normalized to those of vehicle-treated urushiol or oxazolone-challenged mice (Uru + Veh or Oxa + Veh). Control group represents behavior of mice challenged with vehicle (acetone) alone. n = 6–8 mice/group. **P < 0.01 vs. control; ^#P < 0.05, and ^##P < 0.01 vs. Uru + Veh, Uru + Iso IgG, or Oxa + Veh and Oxa + IgG groups. NS, no significance vs. Uru + Veh, Uru + Iso IgG, or Oxa + Veh and Oxa + IgG groups. (E) Schematic protocol for testing the effects of different pharmacological interventions on scratching behavior of urushiol or oxazolone groups of mice. The time scale of day 8 is expanded to visualize treatment and observation time points. (F) Locomotor functions of mice after being treated with different pharmacological reagents mentioned above. Data in bar graphs are expressed as mean ± SEM. n = 6 mice/group. NS, no significance versus Veh group. Student’s t test or 1-way ANOVA followed by Tukey’s post hoc test was used for statistical analysis.