Abstract: | OBJECTIVE: To investigate the acute effects of intravenous administration of cigarette smokeextract (CSE) on histological, inflammatory, and respiratory function parametersin rats, as well as to compare this potential acute lung injury (ALI) model withthat with the use of oleic acid (OA). METHODS: We studied 72 Wistar rats, divided into four groups: control (those injectedintravenously with saline); CSE (those injected intravenously with CSE andsaline); OA (those injected intravenously with saline and OA); and CSE/OA (thoseinjected intravenously with CSE and OA). RESULTS: Mean lung compliance was significantly lower in the OA and CSE/OA groups (2.12 ±1.13 mL/cmH2O and 1.82 ± 0.77 mL/cmH2O, respectively)than inthe control group (3.67 ± 1.38 mL/cmH2O). In bronchoalveolar lavagefluid, the proportion of neutrophils was significantly higher in the OA and CSE/OAgroups than in the control group, as was the activity of metalloproteinases 2 and9. Pulmonary involvement, as assessed by morphometry, was significantly moresevere in the OA and CSE/OA groups (72.9 ± 13.8% and 77.6 ± 18.0%, respectively)than in the control and CSE groups (8.7 ± 4.1% and 32.7 ± 13.1%, respectively),and that involvement was significantly more severe in the CSE group than in thecontrol group. CONCLUSIONS: The intravenous administration of CSE, at the doses and timing employed in thisstudy, was associated with minimal ALI. The use of CSE did not potentiateOA-induced ALI. Additional studies are needed in order to clarify the potentialrole of this model as a method for studying the mechanisms of smoking-induced lunginjury. |