Figure 2.
Absence of Ang-(1-7) vasodilatory response in aortic rings from old females. (a) Concentration–response curves to Ang-(1-7) (10−10 to 10−6 M) in thoracic aortic rings from young (n=10), old (n=16) and old E2-treated (n=5) female mice. Ang-(1-7) induced a concentration-dependent vasodilator effect in young females, but this effect was absent in old females. E2 treatment for seven days (1µg/day) in old females restored Ang-(1-7) response. (b) Concentration–response curves to acetylcholine (10−9 to 10−4 M) in thoracic aortic rings from young (n=5), old (n=8) and old female E2-treated (n=5) mice. (c) Concentration–response curves to Ang-(1-7) (10−10 to 10−6 M) in thoracic aortic rings from young (n=6), young OVX (n=6) and young OVX+E2 (n=6) female mice. Similar to old females, ovariectomized animals have no vasodilatory responses to Ang-(1-7). This response was recovered after E2 replacement. •: young females; ■: young females OVX; □: young females OVX+E2; ○: old females; ◑ : old females E2-treated. ANOVA followed by Newman–Keuls Multiple Comparison post hoc test was performed as statistical analysis. Each point represents the mean ± SEM. *p < 005.