Elastase-induced AAA model.

Male C57BL/6 mice at ∼3 mo of age were randomly assigned to receive water without or with taurine supplementation [1% or 4% (wt/vol)] for 5 days before elastase induction of AAA. Under parenteral anesthesia with pentobarbital, a laparotomy was performed, and the infrarenal abdominal aorta from beneath the left renal vein to the iliac bifurcation was isolated. The isolated segment was tied off, exsanguinated, and then perfused with porcine pancreatic elastase (PPE) type I (E-1250, Sigma) for 5 min. Heat-inactivated elastase was perfused in control mice. In separate experiments, elastase was perfused in WT and MPO^−/− mice. Unless otherwise specified, mice were euthanized 14 days after elastase perfusion for the assessment of aneurysm formation and other parameters, as described below. This protocol was adapted with permission from Thompson et al. (37).