Figure 5. PAR2 activation promotes itch behaviors and Ca²⁺-dependent release of TSLP.

(A) Itch-evoked scratching following injection of tryptase into the cheek (100 pg/20 μL) of wild type (WT; black), PAR2-deficient (blue) or IL7Rα-deficient mice (red), or PBS (white, 20μL) injection into WT mice, n≥8 mice per condition. The time spent scratching was quantified for 1 h after injection. (B) TSLP secretion evoked by 24 h treatment with vehicle (VEH), tryptase (TRY, 100nM), tryptase in the absence of extracellular Ca²⁺ (TRY 0Ca), SLIGRL (100μM), SLIGRL in the absence of extracellular Ca²⁺ (SLIGRL 0Ca), or TG (1μM). n≥4 replicates/condition *P<0.05; **P<0.01;, ***P<0.001. Error bars represent s.e.m.