Modulation of Vascular Function by AMPK: Assessment of NO Bioavailability and Surrogates of Oxidative Stress

The endothelium plays a pivotal role in the development of vascular disease. Decreased bioavailability of nitric oxide, a condition known as "endothelial dysfunction," is considered an early step in this process before atherosclerotic changes of the vessel wall occur. Endothelium-derived nitric oxide (^•NO) may be rapidly scavenged by superoxide anions; therefore, the equilibrium between ^•NO production on one hand and its inactivation by oxidative stress on the other hand is of particular interest. Metabolic enzyme systems such as AMP-activated protein kinase (AMPK) may affect the cellular production of ^•NO or reactive oxygen species (ROS), while AMPK activity itself can also be modulated by ROS. Therefore, the analysis of ^•NO as well as ROS levels is essential to understand how metabolism regulating enzymes like AMPK may modulate vascular disease.