TACR1 and Pruritus: More recently investigated receptors include the interleukin (IL)-31RA and oncostatin-m-specific receptor (OSMR), in addition to the transient receptor potential cation channel subfamily V member 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1), thymic stromal lymphopoietin protein receptor (TSLPR), protease-activated receptor 2 (PAR-2), neurokinin 1 receptor (NK1R), Trk, and histamine (H) 1R and H4R, as well as mas-related G-protein-coupled receptors (MRGPRs) [13,14,15,16,17] that play a role in pruritus mechanisms (Figure 1).