TRPA1 and Dry skin: Our results revealed that the mRNA expression levels of Trpa1 (t8 = 4.798, P = 0.0014), Trpv1 (t8 = 3.258, P = 0.0116), and Trpv4 (t8 = 4.297, P = 0.0026) significantly increased in the DRGs of dry skin-induced chronic itch model (Figure 6C).