关键词: 兔耳, 痤疮模型, 油酸, 毛囊面积, 皮脂腺直径

Abstract: Objective　To optimize existing modeling method and evaluation criteria to improve the uniformity, and reliability of experimental results in the rabbit ear acne model.Methods　Fifteen male New Zealand rabbits were randomly divided into five groups: a blank control group, 50% oleic acid group 1, 50% oleic acid group 2, 75% oleic acid group, and 100% oleic acid group. The inner surface of the rabbit ears were treated daily with the corresponding concentration of oleic acid solution for 14 consecutive days to establish the acne model. After modeling, no intervention was applied, and the recovery was observed for another 14 days. Symptoms at the modeling site were observed daily, ear thickness was measured weekly, and macroscopic scoring was performed. Histopathological examination of ear tissue samples were performed at the end of the modeling period and the recovery period. Additionally, another group of animals was treated with 75% oleic acid to establish the model, followed by the application of 0.1% adapalene gel. Symptoms at the modeling site were observed, ear thickness was measured, and histopathological examination was performed after the treatment.Results　The 75% oleic acid group showed superior macroscopic scores, ear thickness, hair follicle area, sebaceous gland diameter, and histopathological scores compared to the other oleic acid concentration groups. The 0.1% adapalene gel group demonstrated significant improvement in all skin-related indicators after treatment. Conclusion The application of 75% oleic acid to the entire ear successfully established a uniform and stable rabbit ear acne model. The improved macroscopic scoring system and quantitative histopathological evaluation criteria enabled precise and objective assessment of the acne model.

Key words: rabbit ear, acne model, oleic acid, hair follicle area, sebaceous gland diameter