Epidermal prostaglandins after topical application of a tumor promotor.

The topical application of the promoter, 12-O-tetradecanoyl-13-acetate, on the shaved backs of mice was attended by a striking increase in the PGE concentration within epidermis as early as 1 h later. This increase peaked at 24 h but the prostaglandin value remained elevated for at least 48 h. PGF, on the other hand, showed only a modest increase in epidermis with a maximum at 12 h. By 48 h, the PGF concentration returned to normal.