To directly address the specific role of VSMC-derived p38α in AAA, we challenged Sm22Cre,Mapk14f/f, Apoe−/− (SMC-Mapk14 KO) and two different Mapk14 WT control mice, Mapk14f/f, Apoe−/− and Sm22Cre,Mapk14+/+, Apoe−/− with Ang II infusion for 4 weeks. The gene discussed is APOE; the disease is triple-A syndrome.