Figure 3.

Effect of TA on iNOS and NADPH oxidase expression in RVSMCs exposed to H₂O₂. RVSMCs were pretreated with various concentrations of TA (0, 12.5, 25 and 50 µM) for 2 h, followed by the addition of H₂O₂ (100 µM as final concentration) for another 24 h. (A) Proteins were subjected to western blot analysis and (B) the relative protein levels of iNOS, p47phox and NADPH oxidase 1 were analyzed, using GAPDH as the loading control. Data are presented as the mean ± standard deviation obtained from five individual experiments performed in triplicate. ^*P<0.05 vs. untreated control; ^#P<0.05 vs. H₂O₂-treated control. RVSMC, rat vascular smooth muscle cell; TA, tormentic acid; iNOS, inducible nitric oxide synthase; NADPH, nicotinamide adenine dinucleotide phosphate; H₂O₂, hydrogen peroxide; NOX1, NADPH oxidase 1; p47phox, neutrophil cytosolic factor 1; GAPDH, glyceraldehyde 3-phosphate dehydrogenase.