Angiotensin-Converting Enzyme (ACE) is an peptidase that catalyses the conversion of Angiotensin I to Angiotensin II, a potent vasoconstrictor.
ACE can also inactivate bradykinin, a potent vasodilator.
Angiotensin II is a more potent vasoconstrictor than Angiotensin I. Inhibiting ACE to preventing the formation of Angiotensin II (and to some extent, to also prevent the breakdown of bradykinin) is a common strategy to treat high blood pressure.
The ACE gene encodes 2 isozymes. The somatic ACE isozyme is expressed in many tissues, including vascular endothelial cells, renal epithelial cells, and testicular Leydig cells, whereas the germinal ACE isozyme is expressed only in sperms.
ACE is also known as:
peptidyl dipeptidase A
ACE 1 (A second ACE gene, ACE 2 (http://content.nejm.org/cgi/content/extract/347/22/1795), has recently been identified. ACE 2 has direct effects on cardiac function, and is expressed predominantly in vascular endothelial cells of the heart and the kidneys. Whereas ACE 1 converts Angiotensin I to Angiotensin II, which has 8 amino acids, ACE 2 converts Angiotensin I to Angiotensin[1-9], which has 9 amino acids. Whereas Angiotensin II is a potent vasoconstrictor, Angiotensin[1-9] has no effect on blood vessels but can be converted by ACE 1 to a shorter peptide, Angiotensin[1-7], which is a mild vasodilator.)
Multiple Choice Test