[Endothelial dysfunction: a global response].

The endothelium is a dynamic organ involved in the genesis and development of the cardiovascular diseases. Nitric oxide (NO) is one of the factors released from endothelium. NO is generated by endothelial cells through the activity of a constitutive nitric oxide synthase (cNOS). Smooth muscle cells generate NO by an inducible NOS isoform (iNOS). NO regulates vascular tone, different mechanisms involved in the interaction of blood cells to the vascular wall, the growth of smooth muscle cells and the matrix protein synthesis. The lack of an endothelium-dependent vasodilatory response has been defined as endothelial dysfunction. It has been demonstrated a reduced endothelium-dependent vasodilation response in hypertension, aging, atherosclerosis ... and in patients without evident coronary disease. Although the cNOS has been initially described as constitutive, in recent years it has been demonstrated that several pathophysiological stimuli such as hypoxia, chronic exercise, cytokines regulate its level of expression. Our laboratory has demonstrated that an endothelial cytosolic protein regulates the half-lives of eNOS mRNA. This endothelial cytosolic protein could be a target for specific drugs to prevent endothelial dysfunction.