Fig. 4.

Mice with deletion of HIF1-α and HIF2-α in vascular endothelium are not protected against the development of bleomycin-associated pulmonary fibrosis. A: representative images of Masson trichrome-stained lung sections, demonstrating similar degrees of bleomycin-induced pulmonary fibrosis between controls and HIF1/2 KO mice. With the intraperitoneal bleomycin model, lung fibrosis is predominantly peripheral and subpleural. Scale bars: 100 μm at ×20 magnification. B: quantification of degree of fibrosis by scoring on lung sections, with no difference between control and HIF1/2KO mice after bleomycin administration. C: collagen content quantification as determined by microplate hydroxyproline assay of the right lower lobe, showing no difference between control and HIF1/2 KO bleomycin-exposed mice. n = 18 per group.