We pursued a chemogenetic approach to create an animal model of aortic aneurysm formation using a transgenic mouse line DAAO-TGTie2 that expresses yeast D-amino acid oxidase (DAAO) under control of the endothelial Tie2 promoter. In DAAO-TGTie2 mice, DAAO generates the reactive oxygen species hydrogen peroxide (H2O2) in endothelial cells only when provided with D-amino acids. When DAAO-TGTie2 mice are chronically fed D-alanine, the animals become hypertensive and develop abdominal but not thoracic aortic aneurysms. Generation of H2O2 in the endothelium leads to oxidative stress throughout the vascular wall.