Abstract 667: The Role of Aortic Wall-Nuclear Factor- kappa B (NF-kB) Signaling in Formation of Dissecting Aortic Aneurysms

Introduction: Abdominal aortic aneurysm is a devastating disease since it can lead to aortic rupture and instantaneous death. We previously demonstrated that IL-6 secreted from the aortic wall is necessary for the development of abdominal aortic aneurysm and dissection (AAD). Since IL-6 is a NF-kB/RelA dependant gene, we investigated the role of aortic wall- NF-kB/RelA signaling in the development of AAD. Methods and Results: To test the role of aortic wall-RelA, we utilized Cre-Lox technology to delete RelA from aortic cells. Tamoxifen-inducible, Col1a2-promoter driven Cre mice (Col1a2-Cre) were crossed with mT/mG Cre-reporter mice to determine which aortic cells undergo genetic recombination after Cre activation. Flow cytometry analysis of the aortic wall indicated that 88% of the genetically recombined cells were SMCs and 8% were fibroblasts. Next, RelA floxed (RelA f/f) mice, generated in our lab, were crossed with Col1a2-Cre mice. RelA f/f Cre+ and RelA f/f Cre- were stimulated with tamoxifen for 10 ...