Angiotensin converting enzyme

Angiotensin converting enzyme (ACE) is secreted from the lungs, kidneys and vascular endothelium. Wrong statement about ACE is:
1. ACE levels are useful in the diagnosis of sarcoidosis
2. ACE inhibitors are important anti hypertensive agents
3. ACE converts angiotensinogen to angiotensin I
4. ACE degrades bradykinin, a potent vasodilator
Correct answer: 3. ACE converts angiotensinogen to angiotensin I
Angiotensinogen secreted from the liver is converted to angiotensin I by renin secreted by the juxta-glomerular apparatus.
Angiotensin I is converted to angiotensin II from the lungs by ACE. Angiotensin II is a potent vasoconstrictor and hence ACE inhibitors are very useful anti hypertensive agents.
ACE also degrades bradykinin and hence ACE inhibition also helps lowering blood pressure by accumulation of bradykinin which is a potent vasodilator. Accumulation of bradykinin is thought to be the mechanism for ACE inhibitor related cough.
ACE levels are increased in sarcoidosis and is used in diagnosis and follow up of therapy. But it may be worth remembering that ACE levels can also be increased in other conditions like Gaucher’s disease and leprosy.
 

Source: Cardiophile MD - April 20, 2014 Category: Cardiology Authors: Johnson Francis Tags: Cardiology MCQ DM / DNB Cardiology Entrance Source Type: blogs