FIG. 1.

Effect of catalytic antioxidant treatment on acute SM survival and airway cast formation. Animals exposed to 1.4 mg/kg SM were treated with either sterile PBS or 5 mg/kg of AEOL 10150 subcutaneously. Injections began 1 h after animals were disconnected from the exposure apparatus, and repeated every 4, 6, or 8 h, with control (PBS injected) animal data pooled for comparison (median SM PBS survival time was 25 h) (A). At euthanasia, lungs were fixed to quantify airway obstruction (B). Major airway cast scores are presented as mean ± SEM. One-way ANOVA with Newman–Keuls post-test was performed for statistical analysis; significant differences are represented by different letters. To observe the effects of treatment cessation at 48 h post-exposure, animals were treated with the most efficacious dose of antioxidant (5 mg/kg, q4 hours) or PBS (q4 hours) for 48 h, then monitored for an additional 24 h (C) without any treatments (median SM PBS survival time was 38.4 h). Log-rank (Mantel-Cox) tests were performed to compare survival groups, # Significant difference from SM + PBS. The median survival for each 150 treatment group was >48 h (A), and >72 h (C). (A) SM PBS n = 67, SM 10150 q4 hours n = 32, SM 10150 q6 hours n = 12, SM 10150 q8 hours n = 25. (B) Sham n = 12, SM PBS n = 67, SM 10150 q4 hours n = 32, SM 10150 q6 hours n = 12, SM 10150 q8 hours n = 25. (C) SM PBS n = 13, SM 10150 n = 14.