ACE and hypertensive disorder: ACE is a zinc dipeptidylcarboxypeptidase that plays a critical role in the regulation of bloodpressure and cardiovascular function through the renin–angiotensin–aldosteronesystem (RAAS)3 and the kallikrein–kininsystem (KKS).4 In the RAAS, ACE hydrolyzesangiotensin I to form the potent vasoconstrictor angiotensin II, whilein the KKS, ACE converts bradykinin, a potent vasodilator to an inactivefragment.4 Numerous synthetic ACE inhibitors,such as captopril and linosipril, among others, have been used fordecades to treat hypertension.