Figure 2.

Hypoxia increases NOX4 expression in mouse lungs. Mice were exposed to normoxia (Ctr) or hypoxia (10% oxygen, Hyp) for 1 d, and lung tissue was obtained. (A and B) RNA was isolated from normoxic and hypoxic lung tissue. RT-PCR (A) or real-time PCR (B) were performed using specific primers for NOX4 or 18S. NOX4 mRNA levels under normoxia (Ctr) were set to 100%. Data represent % increase of NOX4 mRNA levels compared with control (n = 3; *p < 0.05 vs. Ctr). (C) Protein was isolated and Western blot analysis was performed with antibodies against NOX4 or HIF-1α. Actin levels served as loading control. Data represent % change of protein levels versus normoxic control (100%; n = 3, *p < 0.05 vs. control). (D) Immunohistochemistry was performed on lung tissue samples using antibodies against NOX4, HIF-1α, and α-actin (Actin). Images were taken with a 40x objective. Scale bars, 20 μm.