REN and congestive heart failure: The favourable vascular and endothelial effects of drugs acting on the renin–angiotensin system in CHF depend on a large variety of mechanisms [16,31], such as (1) the reduction in the circulating plasma levels of soluble endothelial adhesion molecules (VCAM-1), (2) the influence of cyclo-oxygenase-dependent vasoconstricting factors, (3) the blockade of bradykinin degradation and (4) the enhanced synthesis of prostaglandins together with augmented release of nitric oxide by endothelial cells.