Metabolism of model organic pollutants in canine respiratory tract mucosa slices
The high incidence of human bronchial tumors has been correlated with the high fractional deposition of inhaled particles in the bronchi. Polycyclic aromatic hydrocarbons (PAHs) are frequently bound to airborne particles due to their low vapor pressures. It is thought that tumorigenicity may result from the release and subsequent bioactivation of these particle-associated organic compounds in the respiratory tract. Previous studies at ITRI examined the clearance of organic toxicants from various regions of the canine respiratory tract. Their results indicated that, while clearance of a highly lipophilic PAH such as benzo(a)pyrene (BaP) from the thin alveolar epithelium took only a few minutes, clearance through the thicker epithelium of the conducting airways took hours. Slower, diffusion-limited clearance results in higher concentrations of lipophilic compounds in the epithelium of the bronchi. Hence, the ability of these tissues to metabolize organic compounds to water-soluble metabolites or reactive intermediates may be extremely important in their clearance from the respiratory tract and the potential susceptibility of this region of the respiratory tract to cancer. The purpose of the present study was to evaluate the ability of bronchial mucosa to metabolize a model organic pulmonary carcinogen, BaP, to reactive and nonreactive metabolites and to evaluate the diffusion of the parent compound and metabolites through the bronchial mucosa.
- Research Organization:
- Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.
- DOE Contract Number:
- AC04-76EV01013
- OSTI ID:
- 54799
- Report Number(s):
- ITRI-144; ON: DE95007526; CNN: Grant RO1-ES05910; TRN: 95:012744
- Resource Relation:
- Other Information: PBD: Nov 1994; Related Information: Is Part Of Inhalation Toxicology Research Institute annual report, October 1, 1993--September 30, 1994; Belinsky, S.A.; Hoover, M.D.; Bradley, P.L. [eds.]; PB: 211 p.
- Country of Publication:
- United States
- Language:
- English
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