Vascular effects following homozygous disruption of p47(phox) - An essential component of NADPH oxidase

Background-Evidence suggests that the vessel wall contains an oxidase simil ar, if not identical, to phagocytic NADPH oxidase, We tested the contributi on of this specific oxidase to the progression of atherosclerosis and the r egulation of blood pressure. Methods and Results-An examination of aortic rings from wild-type mice and mice with homozygous targeted disruptions in p47(phox) revealed that p47(ph ox) knockout mice had a reduction in vascular superoxide production. Howeve r, analyses of apoE -/- p47(phox) +/+ and apoE -/- p47p(hox) -/- strains of mice demonstrated no significant differences in atherosclerotic lesion siz es. Similarly, analyses of wild-type and p47(phox) knockout mice revealed n o differences in either basal blood pressure or the rise in blood pressure seen after the pharmacological inhibition of nitric oxide synthase, Conclusions-NADPH oxidase contributes to basal vascular superoxide producti on. However, the absence of a functional oxidase does not significantly aff ect the progression of atherosclerosis in the standard mouse apoE -/- model , nor does it significantly influence basal blood pressure.