Bradykinin and coronary artery disease

Although the benefits of angiotensin-converting enzyme (ACE) inhibitors in limiting the progression of a variety of cardiovascular diseases are well known, their mechanisms of action have not been completely discovered. A reduction in the synthesis of the potent vasoconstricting agent angiotensin II has for a long time been considered to be the leading mechanism to account for the effects of ACE inhibitors. However, another action of these relatively old drugs is emerging: the increased availability of bradykinin. This kinin, which is broken down by ACE, has potent cardioprotective, antithrombotic antitrophic and vasodilator effects occurring through the stimulation of specific receptors on several cells. The recent development of a specific bradykinin-receptor blocking agent, icatibant, has allowed better understanding of the therapeutic properties of ACE inhibitors mediated by bradykinin both in experimental and clinical studies.