Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Skin Pharmacol Physiol. 2010;23(6):320-7. doi: 10.1159/000313514. Epub 2010 Jun 24.
The Organization for Economic Cooperation and Development (OECD) recommends caffeine as a reference substance for in vitro skin absorption tests using Franz diffusion cells (FDC). However, it has not been possible to investigate the follicular penetration pathway using this method until now. The aim of this study was to develop a technique to allow the examination of the follicular penetration pathway of a substance penetrating into the skin. The OECD standard method was therefore combined with the follicle closing technique (FCT), an established in vivo method. By using test skin of varying follicular densities, different penetration values were obtained for the test substance caffeine. The follicular penetration rate was determined by an indirect calculation after modifying the in vivo FCT for use in the in vitro FDC. This method is the first to allow the differentiation of penetration pathways by combining the OECD standard method (using the FDC) and the FCT. Caffeine showed a surprisingly high rate of penetration through the follicular shunts in vitro.
经济合作与发展组织（经合组织）建议将咖啡因作为使用 Franz 扩散池（FDC）进行体外皮肤吸收测试的参比物质。然而，直到现在，使用这种方法还不可能研究毛囊渗透途径。本研究旨在开发一种技术，以允许检查进入皮肤的物质的毛囊渗透途径。因此，将经合组织的标准方法与毛囊封闭技术（FCT）相结合，该技术是一种已建立的体内方法。通过使用不同毛囊密度的测试皮肤，获得了测试物质咖啡因的不同渗透值。通过修改体内 FCT 用于体外 FDC，间接计算确定了毛囊渗透率。该方法是第一个通过结合经合组织标准方法（使用 FDC）和 FCT 来区分渗透途径的方法。令人惊讶的是，咖啡因在体外通过毛囊旁路的渗透速度非常高。
