特应性皮炎动物模型表皮脂合成的研究

目的:探讨特应性皮炎(AD)皮肤生理改变(包括表皮水分丢失量和角质层水分含量)是否与表皮脂的代谢有关。方法:在小鼠的背部和躯干外涂2,4-二硝基氟苯(DNFB),建立小鼠特应性皮炎模型,利用14[C]乙酸对AD模型表皮脂的代谢进行研究,并用电子显微镜对AD皮肤的超微结构进行观察。结果:AD表皮的胆固醇和脂肪酸的合成速度明显低于对照组,正常对照组的角质细胞间均为正常的复层板层膜结构。而皮炎组的深层角质细胞间虽可见正常的复层板层结构,但有许多没有加工完全的膜结构存在。结论:推测AD皮肤生理的异常改变可能是由于表皮脂的合成减少和角质细胞间膜异常所致。

Decrease of epidermal lipid synthesis in the atopic dermatitis model

Objective: To elucidate whether the skin physiology changes including transepidermal water loss(TEWL) and skin hydration in atopic dermatitis(AD) related to abnormal epidermal lipid metabolism.Methods: The AD animal model was established by repeated topical application of 2,4-dinitro-1-fluocrobenzene to the mouse flanks and ~(14)[C] acetate was used to assess epidermal lipid synthesis.In addition ultrastructural changes were observed with an electron microscope.Results: Both sterol and fatty acid synthesis were significantly decreased in AD epidermis.Normal membrane bilayer structure in the stratum corneum was seen in the control group.In contrast,unprocessed membrane lamellae were present in the intercellular spaces of lower stratum corneum in AD.(Conclusion): The results suggest that both reduction of epidermal lipid synthesis and abnormal membrane bilayers in the stratum corneum account for,at least in part,the skin physiologic change in AD.