Maruotti N et al. - In these diseases the hypoxic environment subsequent to stenosis or occlusion of the vascular lumen is a potent signal for the generation of new blood vessels. Angiogenesis may be a compensatory response to ischemia and to the increased metabolic activity and may be also a further inflammatory stimulus because endothelial cells of newly-formed vessels express adhesion molecules and produce colony-stimulating factors and chemokines for leukocytes.