Influence of spontaneous hypercholesterolemia on elastase-induced experimental AAAs. Following intra-aortic porcine pancreatic elastase (PPE) infusion, normo- (WT) and hypercholesterolemic ApoE−/− mice were monitored for AAA formation and progression via serial ultrasound measurements of maximal infrarenal luminal diameters. (A) Mean and 95% confidence interval (CI) of serum cholesterol concentrations in WT and ApoE−/− mice measured via cholesterol strips. (B) Representative aortic ultrasound images prior to, and 14 days after, PPE infusion in male WT and ApoE−/− mice. (C,D) Mean and 95% CI of maximal infrarenal aortic diameters in male (C) and female (D) WT and ApoE−/− mice at indicated intervals. (E) Presence of sex difference in aneurysmal aortic diameter in WT male and female mice. Mean and 95% CI of maximal infrarenal aortic diameters in WT male and female mice prior to, and indicated days after, PPE infusion. (F) Presence of sex difference in aneurysmal aortic diameter in ApoE−/− male and female mice. Mean and 95% CI of maximal infrarenal aortic diameters in ApoE−/− male and female mice prior to, and indicated days after, PPE infusion. In A, Student’s t-test, ** p < 0.01 compared to male or female WT mice; In (E,F), two-way ANOVA followed by Newman–Keuls post hoc test, ** p < 0.01 compared with WT male or female mice at same timepoints. n = 8 for male WT and ApoE−/− mice; n = 7 and 8 for female WT and ApoE−/− mice, respectively.