Angiotensin converting enzyme (ACE) converts angiotensinogen into angiotensin I ? False ? True
The correct answer and explanation is:
Correct Answer: False
Explanation:
Angiotensin-converting enzyme (ACE) does not convert angiotensinogen into angiotensin I. Instead, renin, an enzyme secreted by the juxtaglomerular cells of the kidney, is responsible for this conversion. Here’s how the renin-angiotensin-aldosterone system (RAAS) works:
- Angiotensinogen Production:
The liver continuously produces a protein called angiotensinogen, which circulates in the bloodstream in an inactive form. - Renin Release and Conversion to Angiotensin I:
When blood pressure drops, sodium levels are low, or sympathetic nervous system activity increases, the kidneys release renin.
Renin then converts angiotensinogen into angiotensin I, which is also an inactive precursor. - ACE Converts Angiotensin I to Angiotensin II:
ACE, which is mostly found in the lungs’ capillaries, converts angiotensin I into angiotensin II, a potent vasoconstrictor.
Angiotensin II plays a major role in increasing blood pressure and stimulating the release of aldosterone from the adrenal glands, which causes sodium and water retention to raise blood volume and pressure.
Summary of the Roles:
- Renin: Converts angiotensinogen → angiotensin I
- ACE: Converts angiotensin I → angiotensin II
So, the statement “ACE converts angiotensinogen into angiotensin I” is false. This misunderstanding can lead to confusion in understanding how medications like ACE inhibitors work. ACE inhibitors block the conversion of angiotensin I to angiotensin II, helping to lower blood pressure by preventing vasoconstriction and fluid retention.
Understanding this pathway is critical in fields like nursing, medicine, and pharmacology, especially in the treatment of hypertension and heart failure.