Fig. 4.

CysLT levels are increased in the skin of the MC903 model of dermatitis and itch. (A) Diagram of procedure: daily application of MC903 on the mouse ear for 12 d. (B) Scratching bouts recorded on days 3, 10, and 12 for 60 min before daily application of vehicle (ethanol) or MC903. (C) Percentage of ear thickness change following daily application of vehicle or MC903. (D) H&E staining performed on ear section at day 12 of MC903 model. (Scale bar: 50 µm.) (E) CysLTs (LTC₄, LTD₄, and LTE₄) levels measured by ELISA at days 3, 6, 10, and 12 (n = 5 to 6). (F and G) Liquid chromatography–mass spectrometry. (F) Representative chromatograms for LTC₄ (Left) and LTE₄ (Right) from ear homogenates at day 12 after daily vehicle treatment (Top) or MC903 treatment (Bottom). (G) LTC₄ and LTE₄ quantification per milligram of ear collected at day 12 after vehicle or MC903 treatment. Values presented as mean ± SEM. Repeated-measures two-way ANOVA, Šidák’s posttest (B and C), two-way ANOVA with Šidák’s posttest (E), and unpaired t test (G). ns, nonsignificant (*P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001).