Mesenteric arteries from obese females were incubated with ER inhibitors for 30 minutes and ACh vasodilation measured. (A) Incubation with the combined ERα and ERβ inhibitor ICI182,780 eliminated the improved dilation previously seen in arteries from obese EC-MR-KO mice. (B) Incubation with vehicle versus the ERα-specific inhibitor MPP in EC-MR-WT arteries and EC-MR-KO arteries. ERα inhibition significantly decreased endothelial-dependent vasodilation in obese EC-MR-KO mice. *p<0.05, 2-way repeated measures ANOVA, Bonferroni post-hoc test. (C) Incubation with vehicle or the ERβ-specific inhibitor PHTPP in obese female EC-MR-WT arteries and obese female EC-MR-KO arteries. ERβ inhibition did not significantly impact vasodilation. 2-way repeated measures ANOVA, Bonferroni post-hoc test. (D) ERα mRNA and (E) protein expression quantified in mesenteric artery tissue from lean and obese EC-MR-WT and EC-MR-KO females. *p<0.05, **p<0.01, 2-way ANOVA, Bonferroni post-hoc test.