Abstract
Skin permeation and its enhancing activity of Coptidis Rhizoma (Coptis japonica MAKINO) were studied in regard to its application as a bath agent. As a result, methanol extracts and three alkaloids (berberine, coptisine, and palmatine isolated from Coptidis Rhizoma) enhanced effectively the skin permeation of 5-fluorouracil, which is taken as a hydrophilic permeant. Furthermore, it was observed that diffusion coefficient is almost constant on the skin permeation of 5-fluorouracil and was also observed that these three kinds of alkaloids did not penetrate through the skin, but adsorbed into the skin. These results suggest that these three protoberberine type alkaloids increase the concentration of polar drugs in the skin and enhance the skin permeation similarly to surfactants.
