title: A novel acoustic evaluation system of scratching in mouse dermatitis: rapid and specific detection of invisibly rapid scratch in an atopic dermatitis model mouse.
abstract: Scratching is an essential and a skin specific behavior induced by itching, which is a common symptom of atopic dermatitis (AD) and other types of dermatitis. Itching sensation and scratching are closely associated and thus scratching times are currently used for evaluating itching in animal models. However, objective measuring systems of scratching to assess the grade of dermatitis and the effectiveness of anti-pruritic drugs in animal dermatitis models are lacking. To investigate a quantitative evaluation system for itching, we have developed a novel acoustic scratching counting system and compared its accuracy with time-consuming slow-motion video recording system. We have also objectively evaluated the efficacy of an antihistamine using this novel system. Scratching behavior of an AD model mouse (K14 driven IL-18 transgenic mouse) was recorded visually and acoustically. Specific scratching sound produced by mice was recorded and counted using a software we have developed, and the results obtained using our acoustic system were not statistically different from data obtained using slow motion video system. Surprisingly, mice scratched more than 10 times/second, which was invisibly rapid motion and revealed inaccuracy of conventional hand counting system. Results were identical to that of measured by 10 times time costing slow-motion video analysis. The antihistamine is clearly effective for suppression of scratching as demonstrated using this objective and accurate method. This novel motion analysis system will open a window for physiological and pathological analysis for animal models and development of anti-pruritic drugs.
authors.affiliation: Department of Dermatology, Mie University, Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie 514-8507, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Umeda
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Noro
authors.forename: Takaaki
authors.initials: T
authors.lastname: Murakami
authors.forename: Kazuya
authors.initials: K
authors.lastname: Tokime
authors.forename: Hitomi
authors.initials: H
authors.lastname: Sugisaki
authors.forename: Keiichi
authors.initials: K
authors.lastname: Yamanaka
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kurokawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kuno
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tsutsui
authors.forename: Kenji
authors.initials: K
authors.lastname: Nakanishi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Mizutani
mesh_terms: D000818:Animals; D003876:Dermatitis, Atopic / Q000503:physiopathology*; D004195:Disease Models, Animal; D006614:Hindlimb; D006801:Humans; D053547:Keratin-14 / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D015588:Observer Variation; D011537:Pruritus / Q000503:physiopathology*; D014743:Videotape Recording
chemical_list: C507540:KRT14 protein, human; D053547:Keratin-14