Jiang Shao Jun, Zhou Xiao Jun
Department of Pathology, Jinling Hospital, 305 Zhong Shan Dong Lu, Nanjing 210002, P.R. China.
Biol Pharm Bull. 2003 Jan;26(1):66-8. doi: 10.1248/bpb.26.66.
The epidermal permeability barrier appears to be regulated primarily by the lamellar arrangement of lipid bilayers between coneocytes of the stratum corneum and presents a significant barrier to the transdermal delivery of drugs. The aim of the present study was to investigate the effects of oleic acid on the ultrastructure of stratum corneum lipids in rat skin. Wistar rats were treated topically with 10% oleic acid/propylene glycol for 2 h, the structure of stratum corneum was examined by electron microscopy using osmium tetroxide or ruthenium tetroxide postfixation, and the epidermal barrier function was evaluated in a lanthanum tracer study. Ultrastructural examination revealed that there was a marked alteration in the stratum corneum and the tracer penetrated into the intercellular spaces of the stratum corneum after application of oleic acid. These results suggest that ruthenium tetroxide postfixation is a powerful tool for the study of the stratum corneum lipid structure. Oleic acid might increase the epidermal permeability through a mechanism involving the perturbation of stratum corneum lipid bilayers and lacunae formation to enhance transdermal drug delivery.
表皮渗透屏障似乎主要由角质层角质形成细胞之间脂质双分子层的片状排列所调节，并且对药物的透皮递送构成显著屏障。本研究的目的是调查油酸对大鼠皮肤角质层脂质超微结构的影响。将10%油酸/丙二醇局部应用于Wistar大鼠2小时，使用四氧化锇或四氧化钌后固定通过电子显微镜检查角质层结构，并在镧示踪研究中评估表皮屏障功能。超微结构检查显示，应用油酸后角质层有明显改变，示踪剂渗入角质层的细胞间隙。这些结果表明，四氧化钌后固定是研究角质层脂质结构的有力工具。油酸可能通过涉及扰乱角质层脂质双分子层和形成腔隙的机制增加表皮通透性，以增强透皮药物递送。
