[Asymmetric dimethyl arginine (ADMA): a novel cardiovascular risk factor?].

Functional changes of the vessel wall--specifically dysfunction of endothelial cells--may precede the formation of frank plaques at the initiation of atherosclerosis. Clinically endothelial function and dysfunction can be measured by angiography or ultrasound techniques. Another possibility is the measurement of circulating markers of endothelial dysfunction in human plasma, such as the endogenous NOS inhibitor ADMA (asymmetric dimethylarginine). In our recent studies we were able to show that ADMA accumulates in the presence of metabolic changes such as hyperhomocysteinemia, insulin resistance and type-2 diabetes, and that these elevations of plasma ADMA correlate well with the amount of endothelial dysfunction and with NO bioavailability. Furthermore ADMA was shown to be dynamically regulated and to play an important patho-physiologic role in myocardial ischemia and reperfusion. Thus, measurements of plasma ADMA in patients could help to screen for manifestations of atherosclerosis. Moreover attempts to reduce plasma and tissue ADMA could potentially play an important role in the treatment of endothelial dysfunction, atherosclerosis, but also of ischemia reperfusion injury.