TKTL1 and bronchopulmonary dysplasia: To determine whether Nintedanib, a tyrosine kinase receptor (TKR) inhibitor, could serve as a novel preventive strategy for BPD, we first examined dose-related effects of Nintedanib on the developing lung in neonatal rats and found that administration of high but not low dose Nintedanib impaired lung airspace growth and caused early death.