Fig. 4.

Effects of hypoxia and cartilage oligomeric matrix protein (COMP) on the expression of NADPH oxidases NOX2 and NOX4 detected by Western blotting. Bovine pulmonary artery (BPA) were cultured under 21% (CTL) or 3% O₂ (H48) for 48 h in the absence and presence of COMP (0.5 μM). A and B: representative Western blot bands and quantitative analysis of changes in NOX2 (A) and NOX4 (B). *P < 0.05, two-way ANOVA with Sidak correction, n = 7. C: effects of siRNA knockdown of COMP on detection of NOX2 (n = 8) and NOX4 (n = 6) protein levels. Representative Western blot bands and quantitative analysis of NOX2 and NOX4. **P < 0.01, ***P < 0.001, COMP siRNA vs. scramble siRNA, paired t test. (H48 + C, 3% O₂ for 48 h and treated with 0.5 μM COMP at the same time; COMPi, COMP siRNA.)