Gloor M, Gehring W
Hautklinik am Klinikum der Stadt Karlsruhe gGmbH.
Hautarzt. 2003 Apr;54(4):324-30. doi: 10.1007/s00105-003-0512-7. Epub 2003 Feb 28.
The appearance of the skin depends greatly on the hydration of the stratum corneum which is regulated by water binding substances of the corneocytes and also by the quality of the stratum corneum lipids. Furthermore these lipids are responsible for the barrier function. In patients with atopic dermatitis, the water binding capacity and the barrier function of the stratum corneum are reduced even in clinically healthy skin areas. Emollients can damage the stratum corneum and lead to desiccation and a disturbance of the barrier. This effect is a result of an increased permeability of the barrier lipids and direct damage to the keratinocytes and corneocytes. The degree of damage of the barrier caused by emollients in dermatological vehicles has not been sufficiently investigated. As suggested by hypothetical considerations, such an effect is not expected and cannot be demonstrated in water-in-oil-emulsions. Oil-in-water-emulsions without glycerol as well as lipophilic and hydrophilic microemulsions do damage the barrier function. Both types of microemulsions additionally lead to a dehydration of the stratum corneum. The damaging effect of oil-in-water-emulsions can be reduced by the addition of glycerol and urea.
皮肤的外观很大程度上取决于角质层的水合作用，这由角质形成细胞中的水结合物质以及角质层脂质的质量来调节。此外，这些脂质还负责屏障功能。在特应性皮炎患者中，即使在临床健康的皮肤区域，角质层的水结合能力和屏障功能也会降低。润肤剂会损害角质层，导致皮肤干燥和屏障功能紊乱。这种效应是屏障脂质通透性增加以及对角质形成细胞和角质形成细胞直接损伤的结果。皮肤科制剂中的润肤剂对屏障造成的损害程度尚未得到充分研究。根据假设性考虑，在油包水乳液中预计不会出现这种效应，也无法证实。不含甘油的水包油乳液以及亲脂性和亲水性微乳液确实会损害屏障功能。这两种类型的微乳液还会导致角质层脱水。通过添加甘油和尿素，可以降低水包油乳液的损害作用。
