Characterization of a 2,4-dinitrochlorobenzene-induced chronic dermatitis model in rats.
Although many mouse models of atopic dermatitis have been reported, few rat models have been studied. In this study, a rat chronic allergic dermatitis model was developed and evaluated as a pharmacological model of atopic dermatitis. Prominent ear thickening and scratching were induced after the application of 2,4-dinitrochlorobenzene to the right ear of Brown Norway rats 3 times per week for 3 weeks. Histopathologically, infiltration of T cells in the ear was observed on day 7, and eosinophils and mast cells were found in addition to T cells on day 21. The expression of interferon-gamma and interleukin-4 was increased on day 7 when compared with normal rats. However, interferon-gamma expression had disappeared by day 21. Tacrolimus ointment applied after ear tissue thickening fully developed, suppressed chronic dermatitis in a dose-dependent manner. This model has some symptomatic and histopathological similarities to atopic dermatitis and might be useful in pharmacological studies.
Fujii
Y
Y
Applied Pharmacology Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Osaka, Japan. yasutomo.fujii@jp.astellas.com
Takeuchi
H
H
Sakuma
S
S
Sengoku
T
T
Takakura
S
S
D000818:Animals; D002908:Chronic Disease; D003876:Dermatitis, Atopic / Q000139:chemically induced* / Q000276:immunology / Q000473:pathology; D004137:Dinitrochlorobenzene / Q000008:administration & dosage / Q000633:toxicity*; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D004423:Ear; D006241:Haptens / Q000008:administration & dosage / Q000633:toxicity; D008297:Male; D051381:Rats; D011914:Rats, Inbred BN; D013997:Time Factors
D004137:Dinitrochlorobenzene; D006241:Haptens