Immunohistochemistry for Cre recombinase, HIF1α, and
HIF2α. Lung sections from control (A-C) and
HIF1αΔ/Δ pups (D-F) were immunostained
for Cre recombinase (A and D), HIF1α (B and
E), and HIF2α (C and F). Immunohistochemistry
for Cre recombinase shows strong staining of
HIF1αΔ/Δ mouse alveolar epithelial cells (D,
brown color). Positively stained cells for HIF1α and HIF2α
are depicted by solid arrows. HIF1αΔ/Δ
pups show decreased expression of HIF1α and HIF2α as compared with
control littermates. a, air space; p, pleural surface;
s, septa. All doxycycline treatments were for at least 12 days.