Temporal expression levels of BMPR2 isoforms following BLM exposure in mice. Expression levels of BMPR2 isoform A (A), BMPR2 isoform B (B), or calculated ratio of isoform A relative to isoform B (C), from lung lysates from PBS- (day 33) or BLM-exposed mice on days 14, 21, and 25. **0.001 < P < 0.01, ***P ≤ 0.01, ANOVA comparisons between PBS and BLM treatment groups.