Angiotensin-converting enzyme: a well-known stranger. Part II

Abstract

The angiotensin-converting enzyme (ACE) is constitutively expressed on the surface of endothelial, epithelial and immune system cells (macrophages, dendritic cells). The lungs are believed to be the main source of circulating ACE. However, other organs such as the small intestine, kidneys, heart, brain, epididymis, and prostate have also been found to express ACE at levels comparable to those in the lungs. ACE expression is regulated not only passively by the number of endothelial cells, but also by endothelial function. In general, the biochemical environment is the driving force behind the enzymatic activity of ACE, influencing cells capable of expressing ACE and regulatory proteins. The discovery of tissue ACE has changed our understanding of the pathophysiology of many diseases. In particular, it turned out that renal versus circulating ACE is more important in the development of arterial hypertension, diabetic nephropathy, acute and chronic kidney disease.