cowhage-induced itch as an experimental model for pruritus. a comparative study with histamine-induced itchcowhage-induced外阴瘙痒作为实验模型。.pdfVIP

Cowhage-Induced Itch as an Experimental Model for Pruritus. A Comparative Study with Histamine-Induced Itch 1. 1. 2 1 1,2,3 Alexandru D. P. Papoiu , Hong Liang Tey , Robert C. Coghill , Hui Wang , Gil Yosipovitch * 1 Department of Dermatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, United States of America, 2 Department of Neurobiology and Anatomy, Wake Forest University School of Medicine, Winston-Salem, North Carolina, United States of America, 3 Department of Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina, United States of America Abstract Background: Histamine is the prototypical pruritogen used in experimental itch induction. However, in most chronic pruritic diseases, itch is not predominantly mediated by histamine. Cowhage-induced itch, on the other hand, seems more characteristic of itch occurring in chronic pruritic diseases. Objectives: We tested the validity of cowhage as an itch-inducing agent by contrasting it with the classical itch inducer, histamine, in healthy subjects and atopic dermatitis (AD) patients. We also investigated whether there was a cumulative effect when both agents were combined. Methods: Fifteen healthy individuals and fifteen AD patients were recruited. Experimental itch induction was performed in eczema-free areas on the volar aspects of the forearm, using different itch inducers: histamine, cowhage and their combination thereof. Itch intensity was assessed continuously for 5.5 minutes after stimulus application using a computer- assisted visual analogue scale (COVAS). Results: In both healthy and AD subjects, the mean