Expression of p22-phox and gp91-phox, essential components of NADPH oxidase, increases after myocardial infarction

Recent studies have shown that oxidative stress plays an important role in cardiovascular diseases. NADPH oxidase is one of the major sources of super oxide anions and a candidate for the initiation and development of atherosc lerosis, which involves the remodeling of vasculature. However, the relevan ce of NADPH oxidase in ventricular remodeling has not been well-characteriz ed. This is the first report showing that the expression of p22-phox and gp 91-phox, essential components of NADPH oxidase, are increased in the infarc ted sites after myocardial infarction. The levels of thiobarbituric acid re active substance, which indicates the lipid peroxidation level, and nuclear factor-kappaB (NF-kappaB) DNA binding activity are also increased in infar cted sites. Our results suggest that the increased expression of NADPH oxid ase may have an effect on left ventricular remodeling by increasing the red ox-sensitive NF-kappaB DNA binding activity as well as the lipid peroxidati on level. (C) 2001 Academic Press.