title: Metabolic activation of halogenated hydrocarbons in the conjunctival epithelium and excretory ducts of the intraorbital lacrimal gland in mice.
abstract: Autoradiographic studies were performed to determine the localization of irreversibly bound radioactivity in the eyes and accessory structures of mice exposed to 14C-labelled organic solvents in vivo or in vitro. A selective localization of bound radioactivity was observed in the conjunctival epithelium of mice given i.v. injections of 1,2-dibromoethane, chloroform, carbon tetrachloride or bromobenzene. Similar results were observed after instillation of chloroform or carbon tetrachloride in the conjunctival sac and after incubation of eyelids with the labelled compounds in vitro. A high level of irreversibly bound radioactivity was also observed in the excretory ducts of the intraorbital lacrimal glands of mice exposed to 1,2-dibromoethane in vivo and in vitro. After incubation of 14C-labelled 1,2-dibromoethane or chloroform with homogenates prepared from rat conjunctiva, the presence of irreversibly protein-bound radioactivity was detected. The results indicate that the conjunctival epithelium can metabolically activate halogenated organic solvents into products that bind to the tissue. The significance of a metabolic activation of chemicals in the pathogenesis of chemically induced lesions in the conjunctiva merits further attention.
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala.
authors.forename: E B
authors.initials: EB
authors.lastname: Brittebo
authors.forename: C
authors.initials: C
authors.lastname: Eriksson
authors.forename: I
authors.initials: I
authors.lastname: Brandt
mesh_terms: D000818:Animals; D001345:Autoradiography; D001711:Biotransformation; D001969:Bromobenzenes / Q000493:pharmacokinetics; D002251:Carbon Tetrachloride / Q000493:pharmacokinetics; D002725:Chloroform / Q000493:pharmacokinetics; D003228:Conjunctiva / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D015946:Ethylene Dibromide / Q000493:pharmacokinetics; D005143:Eyelids / Q000378:metabolism; D005260:Female; D006846:Hydrocarbons, Halogenated / Q000493:pharmacokinetics*; D066298:In Vitro Techniques; D007765:Lacrimal Apparatus / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D001969:Bromobenzenes; D006846:Hydrocarbons, Halogenated; D015946:Ethylene Dibromide; D002725:Chloroform; D002251:Carbon Tetrachloride; C032036:bromobenzene