Nesiritide is broken down by
**Core Concept**
Nesiritide is a synthetic B-type natriuretic peptide (BNP) analogue used in the treatment of acute decompensated heart failure. It works by stimulating guanylate cyclase, leading to vasodilation and natriuresis.
**Why the Correct Answer is Right**
Nesiritide is broken down by Neprilysin, a metalloprotease enzyme that cleaves and inactivates various peptides, including natriuretic peptides. This degradation process is essential for regulating the activity of BNP and its analogues. The breakdown of nesiritide by Neprilysin limits its duration of action and is a key factor in its pharmacokinetics.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as there is no established mechanism by which nesiritide is broken down by Aminopeptidases.
* **Option B:** This option is incorrect as there is no established mechanism by which nesiritide is broken down by Angiotensin-Converting Enzyme (ACE).
* **Option D:** This option is incorrect as there is no established mechanism by which nesiritide is broken down by Monoamine Oxidase (MAO).
**Clinical Pearl / High-Yield Fact**
Nesiritide's short duration of action due to Neprilysin-mediated breakdown is a key factor in its clinical use. This property allows for rapid titration of the drug to achieve optimal therapeutic effects in patients with acute heart failure.
**Correct Answer: C. Neprilysin**