NOS3 and stricture: The role of NOS3 in adult development of aortic aneurysm, coarctation or aortic valve stenosis is not clear as aortic wall NOS expression is lower in bicuspid aortic aneurysm [98] and in the aortic root [99] but not associated with aortic stenosis or aneurysm in NOS3−/− mice [100].