The production of iNOS‐derived NO has previously been shown to increase the expression and activities of elastolytic MMP‐2 and MMP‐9.35 Further, the presence of the activated forms of MMP‐2 and MMP‐9 has also been reported in patients with aortic aneurysms and implicated in the degradation of the extracellular matrix.36 To assess this possibility, we studied the expression of these enzymes and their respective inhibitors. This evidence concerns the gene NOS2 and aortic aneurysm.