title: Epithelial binding of hexachlorocyclohexanes in the respiratory and upper alimentary tracts: a comparison between the alpha-, beta- and gamma-isomers in mice.
abstract: The tissue distribution of the alpha-, beta- and gamma-isomers of 14C-labelled hexachlorocyclohexane (HCH) in pregnant mice was studied by whole-body and light microscopic autoradiography. The results showed that alpha-, beta- and gamma-HCH are taken up and retained in adult and foetal surface epithelia to varying degrees. Autoradiography of organic-solvent extracted tissue sections of nonpregnant mice given gamma-HCH (lindane) demonstrated that a high level of tissue-bound radioactivity was present in the tracheobronchial epithelium, the subepithelial glands in the olfactory mucosa, the squamous epithelia of the tongue, oesophagus, forestomach and vagina, the inner zone of the adrenal cortex, and the liver. Autoradiography of freeze-dried sections of pregnant mice given alpha- or beta-HCH showed preferential localization of radioactivity in the nasal and tracheobronchial epithelia after administration of both isomers, whereas localization of radioactivity in the epithelia of the tongue and oesophagus was only observed after administration of alpha-HCH. The results suggest that the localization of HCH isomers and/or their metabolites in the epithelial linings is regulated by factors that are highly substrate specific.
mesh_terms: D000818:Animals; D004064:Digestive System / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D001556:Hexachlorocyclohexane / Q000378:metabolism*; D007536:Isomerism; D051379:Mice; D012137:Respiratory System / Q000378:metabolism*; D014018:Tissue Distribution; D014059:Tongue / Q000378:metabolism; D014621:Vagina / Q000378:metabolism
chemical_list: D001556:Hexachlorocyclohexane