ACE

Angiotensin I Converting Enzyme (ACE, also known as peptidyl-dipeptidase A, kininase II, or CD143) is a type I transmembrane zinc metallopeptidase that is important in the metabolism of the vaso-active peptides angiotensin II and bradykinin. Two isoforms of ACE that exhibit distinct physiologic functions have been described: germinally expressed ACE (gACE) and somatic cell expressed ACE (sACE). Both isoforms are transcribed from a single gene using alternative promoters. The gACE isoform is exclusively expressed in the testes, whereas sACE is expressed on endothelial cells, epithelial cells, neuronal cells, and dendritic cells. A soluble form of CD143 is likely shed from endothelial cells and is found in serum, plasma, seminal fluid, amniotic fluid and cerebral spinal fluid. Functionally, CD143 has a role in blood pressure regulation, electrolyte balance, reproduction, cardiovascular disease, kidney disease, cancer and Alzheimer’s disease. Inhibitors of ACE are used clinically to treat hypertension, cardiac failure, and diabetic retinopathy.