Reserpine lowers blood pressure by depleting peripheral and central catecholamine stores. Its molecular target is:
- A The vesicular monoamine transporter (VMAT2) on storage granule membranes ✓
- B The norepinephrine reuptake transporter (NET) at the nerve terminal membrane
- C Tyrosine hydroxylase, the rate-limiting enzyme of catecholamine synthesis
- D Postsynaptic alpha-2 receptors in the vasomotor center
Correct answer: A. The vesicular monoamine transporter (VMAT2) on storage granule membranes
Explanation
Reserpine binds irreversibly to VMAT2 on the membranes of amine storage vesicles, blocking uptake of norepinephrine and dopamine into vesicles; cytoplasmic transmitter is then destroyed by mitochondrial MAO, leading to prolonged depletion lasting days to weeks after a single dose. NET blockade describes cocaine and tricyclics, tyrosine hydroxylase inhibition describes metyrosine, and central alpha-2 agonism is the mechanism of methyldopa metabolites and clonidine.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.