Angiotensin-Converting Enzyme Inhibitors as of May 10, 2001

Angiotensin-Converting Enzyme Inhibitors as of May 10, 2001

Among angiotensin-converting enzyme inhibitors, captopril (mercaptophenylproline) is the most widely used clinically. Its main action is on the renin-angiotensin-aldosterone system. It inhibits the conversion of angiotensin I to angiotensin II, thereby suppressing vasoconstriction, reducing aldosterone secretion, and eliminating water and sodium retention. In addition to captopril, there are second-generation products such as ramipril, enalapril, and trandolapril, all of which are administered at lower doses—5–10 mg three times daily. The primary function of this group of drugs is to block the production of angiotensin. Angiotensin II (Ang II) is a powerful vasoconstrictor and growth stimulator for the cardiovascular system; it can reduce left ventricular ejection fraction and promote cardiac remodeling. Angiotensin II has receptors, and its effects are only realized after receiving relevant signals, which led to the development of angiotensin II receptor blockers (ARBs). Losartan and valsartan are representative examples. These drugs not only share the characteristics of ACEIs (angiotensin-converting enzyme inhibitors) but also appear to have a more pronounced effect on improving cardiac dynamics.