Loss of S1PR3 attenuates scratching behaviors in mice in the imiquimod model of psoriasis, but not in the MC903 model of atopic dermatitis

Here we examine the role of sphingosine 1-phosphate receptor 3 (S1PR3) in chronic itch. We used 2 mouse models—the MC903 model of atopic dermatitis and the imiquimod model of psoriasis—to examine the contribution of S1PR3 to chronic itch. We measured scratching behaviors in these mouse models in S1PR3−/−, +/−, and +/+ animals. Whereas we observed no effect of loss of S1PR3 on itch behaviors in the MC903 model, imiquimod-evoked itch behaviors were reduced in S1PR3−/− animals. Overall, the data support a role for S1PR3 signaling in the development of psoriatic but not atopic itch.