ABSTRACT
Objective The aim of this study was to investigate the mechanism underlying pruritus by comparing the epidermal growth factor receptor inhibitor(EGFRI)-erlotinib mouse model with the substance P(SP)-induced pruritus mouse model. Methods Two randomized groups of mice were treated with erlotinib or SP to induce pruritus. Behavioral and skin manifestations were observed. Pathological images and neurokinin 1 receptor(NK-1R)expression of the skin were determined. Concentration of interleukin(IL)-31, IL-33, histamine, leukotriene B4, and SP was analyzed by enzyme-linked immunosorbent assay. Nitric oxide was analyzed by colorimetry. Results Transient pruritus induced by erlotinib appeared 2 to 5 days after treatment. In contrast, continuous pruritus was observed during the first hour, but was then gradually relieved. These two shared similar scratching behavior. Concentration of neurotransmitters showed similar trends in changes among the erlotinib group and SP group. Immunohistochemical expression was also consistent between the erlotinib group and SP group. Conclusions Erlotinib-associated pruritus is related to release of signaling factors through the SP/NK-1R signaling pathway.