Effect of papain-induced emphysema on permeability of rat lung to drugs.
To investigate the effect of a papain-induced emphysema-like condition on pulmonary absorption of drugs, rats were exposed to either papain aerosol or distilled water aerosol (control) intermittently for 2 wk, and rates of drug absorption from damaged and control lungs were compared. To measure absorption rates, 0.1 ml of drug solution (0.1-10 mM) was administered through a tracheal cannula to anesthetized animals, and after various times lungs were assayed for unabsorbed compound. In absorption experiments with the lipoid-insoluble compounds, mannitol, p-aminohippuric acid, and procaine amide ethobromide, all three drugs were absorbed from the lungs about twice as rapidly in papain-treated rats as in control. In contrast, procaine amide, a relatively lipoid-soluble drug, was absorbed at the same rate in both control and papain-treated animals. The results suggest that papain-induced lung damage increases the porosity of the pulmonary epithelium.
D000336:Aerosols; D000618:Aminohippuric Acids / Q000378:metabolism*; D000818:Animals; D008168:Lung / Q000032:analysis / Q000378:metabolism* / Q000473:pathology; D008353:Mannitol / Q000378:metabolism*; D009929:Organ Size; D010206:Papain; D010539:Permeability; D011342:Procainamide / Q000378:metabolism*; D011656:Pulmonary Emphysema / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D051381:Rats
D000336:Aerosols; D000618:Aminohippuric Acids; D008353:Mannitol; D010206:Papain; D011342:Procainamide