ndothelial Nitric Oxide Synthase in Bicuspid ortic Valve Disease

Background. The pathogenesis of ascending aortic di-latation in the presence of a bicuspid valve is discussed controversially. Recent experimental evidence suggests that the expression of endothelial nitric oxide synthase (eNOS) may have an influence on aortic valve anatomy and aneurysmal dilatation of the aorta. We investigated the relationship among eNOS expression, valve anatomy, and aortic dilatation in the human aortic wall. Methods. Aortic wall specimens from 39 patients with aortic valve disease (bicuspid, n ‫؍‬ 17; tricuspid, n ‫؍‬ 22) were studied. The functional aortic valve pathology was regurgitation (n ‫؍‬ 22), stenosis (n ‫؍‬ 10), and combined aortic valve disease (n ‫؍‬ 7). The specimens were obtained intraoperatively from the aortic wall above the noncoro-nary sinus. The eNOS protein expression was quantified by western blot analysis after immunoprecipita-tion from tissue lysates. The eNOS levels were