title: Long persistence of monofunctional 8-methoxypsoralen-DNA adducts in human skin in vivo.
abstract: Human skin can be persistently photosensitized by topical application of aqueous 8-methoxypsoralen plus immediate irradiation with a non-erythemogenic dose of wavelengths above 380 nm. Re-exposure of skin thus sensitized to broadband UV-A produces phototoxic erythema 72-120 h later. The persistence of the photosensitization was demonstrated by phototoxic erythema after re-exposure up to 15 days after the first sensitizing irradiation. According to the concept that the first exposure induces primarily psoralen monoadducts, we consider this an investigation of psoralen monoadduct persistence. In contrast to several earlier studies, this sensitive method indicates that psoralen monoadducts may remain in human skin in vivo for more than 2 weeks after formation.
authors.affiliation: Wellman Laboratories of Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston 02114.
authors.forename: B
authors.initials: B
authors.lastname: Ortel
authors.forename: D J
authors.initials: DJ
authors.lastname: Maytum
authors.forename: R W
authors.initials: RW
authors.lastname: Gange
mesh_terms: D004247:DNA / Q000378:metabolism / Q000528:radiation effects*; D006801:Humans; D008027:Light; D008730:Methoxsalen / Q000378:metabolism*; D012867:Skin / Q000378:metabolism / Q000528:radiation effects*; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D004247:DNA; D008730:Methoxsalen