Figure 2. Vascular oxidative stress induced by deletion of smooth muscle Sod3 promotes age-related aortic stiffening and hypertension.

(A) Masson’s trichrome blue staining in 3-, 6-, and 9-month-old Sod3^fl/fl Cre^– and Sod3^fl/fl Smmhc-Cre mice. Tamoxifen was administered at 3 mg/20 kg in corn oil via i.p. injection at 10 weeks of age. Images are ×20 magnification. Scale bars: 100 μm. (B) Aortic hydroxyproline content. (C and D) Pressure diameter relationship and stress-strain relationships. (E and F) Blood pressure measured by radiotelemetry (n = 6–8). ^#P < 0.05 vs. Cre^–/–; *P < 0.05 vs. Sod3^fl/fl Smmhc Cre 3 month; **P < 0.05 vs. Sod3^fl/fl Smmhc-Cre 3 month. Aortic hydroxyproline content was analyzed using 2-way ANOVA. Pressure diameter relationships, stress-strain relationships, and blood pressures were analyzed using 1-way ANOVA with repeated measures.