title: Anthranoid free radicals found in pseudomelanosis coli.
abstract: Pseudomelanosis coli occurs after prolonged intake a anthranoids. After discontinuation of intake the pigmentation disappears apparently without noxious effects, including carcinogenicity and genotoxicity. We are presenting ESR spectra of pseudomelanosis coli specimen, compared to ESR spectra of pigmented skin scales taken from psoriatic patients treated topically with anthralin, and with ESR spectra of anthralin brown material formed in vitro. The ESR spectra show comparable g values within the accuracy of measurements. The examined specimens reveal remarkable stability: the intensity of the ESR signal remained practically constant over the period of four years. The chemical and physicochemical properties of the brown pigments formed from anthranoids explain the observed bio-inertness of these materials including that of melanosis coli pigment derived from anthranoids.
authors.affiliation: Faculty of Pharmacy, University of Ljubljana, J. Stefan Institute, Slovenia, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Krbavcic
authors.forename: S
authors.initials: S
authors.lastname: Pecar
authors.forename: M
authors.initials: M
authors.lastname: Schara
authors.forename: K
authors.initials: K
authors.lastname: Müller
authors.forename: W
authors.initials: W
authors.lastname: Wiegrebe
mesh_terms: D000287:Administration, Topical; D000875:Anthralin / Q000009:adverse effects* / Q000378:metabolism*; D000893:Anti-Inflammatory Agents / Q000009:adverse effects / Q000627:therapeutic use; D002400:Cathartics / Q000009:adverse effects* / Q000378:metabolism*; D003106:Colon / Q000737:chemistry; D003108:Colonic Diseases / Q000139:chemically induced* / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006801:Humans; D007413:Intestinal Mucosa / Q000737:chemistry*; D011565:Psoriasis / Q000188:drug therapy / Q000378:metabolism; D012867:Skin / Q000737:chemistry
chemical_list: D000893:Anti-Inflammatory Agents; D002400:Cathartics; D005609:Free Radicals; D000875:Anthralin