title: Influence of elastase-induced emphysema and the inhalation of an irritant aerosol on deposition and retention of an inhaled insoluble aerosol in Fischer-344 rats.
abstract: The purpose of this study was to assess the effects of elastase-induced pulmonary emphysema and the inhalation of an irritant aerosol (Triton X-100, a nonionic surfactant similar to those used in a number of pressurized consumer products) on pulmonary deposition and retention of an insoluble test aerosol, 59Fe-labeled Fe2O3. Untreated rats or rats pretreated by intratracheal instillation with elastase were exposed to an aerosol of 59Fe-labeled Fe2O3 either 18 hr or 7 days after exposure to aerosolized Triton X-100 which was administered in doses of 20, 100, or 200 micrograms/g of lung. Rats pretreated with elastase had significantly lower pulmonary deposition of 59Fe than the untreated controls (p less than 0.005). Pulmonary deposition of Fe2O3 was unaffected by pretreatment with Triton X-100. Elastase treatment alone had no effect on retention of Fe2O3. Triton X-100 administered 18 hr prior to exposure of rats to Fe2O3 aerosol resulted in dose-related increases in whole-body retention of 59Fe. When rats were exposed to Triton X-100 7 days before exposure to Fe2O3, increased retention of 59Fe was noted only in those treated at the highest Triton X-100 dose level (200 micrograms/g).
mesh_terms: D000336:Aerosols; D000818:Animals; D005290:Ferric Compounds / Q000378:metabolism; D008168:Lung / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D017830:Octoxynol; D010196:Pancreatic Elastase / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000633:toxicity*; D011656:Pulmonary Emphysema / Q000139:chemically induced / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D012995:Solubility
chemical_list: D000336:Aerosols; D005290:Ferric Compounds; C000499:ferric oxide; D011092:Polyethylene Glycols; D017830:Octoxynol; D010196:Pancreatic Elastase