Pulmonary effects of inhaled diesel particles in rats

The pulmonary response to inhalation exposure to diesel exhaust particles (DEP) was investigated in a rat model. Adult male Sprague-Dawley rats were exposed by whole-body inhalation to air or an aerosol containing DEP at concentrations of 200 or 1000 mg/m3, 6 hours/day for 4 days. The control and DEP-exposed rats were euthanized at post-exposure time intervals of 1, 7, or 27 days and pulmonary inflammatory, cytotoxic and oxidant responses were determined. Analysis of bronchoalveolar lavage parameters of toxicity such as lactate dehydrogenase activity, oxidant generation, and inflammation did not reveal any significant pulmonary toxicity in the DEP-exposed rats. The lung gene expression profiles did not change significantly in the DEP exposed rats compared with the controls. The data obtained from the present study demonstrated that DEP inhalation exposure under the conditions employed in the present study did not result in any significant lung toxicity in the rats. Overall design: The rats were exposed by whole-body inhalation to filtered air or an aerosol containing DEP at concentrations of 200 or 1000 ug/m3, 6 hours/day for 4 days. The control and DEP-exposed rats were euthanized at post-exposure time intervals of 1, 7, or 27 days. Lung samples (n=6) were used to determine gene expression profiles by RNA sequencing.