Sodium valproate inhibits which enzyme to elevate brain GABA levels, contributing to its antiepileptic effect?
- A GABA transaminase ✓
- B Glutamic acid decarboxylase
- C Monoamine oxidase B
- D Succinic semialdehyde dehydrogenase only
Correct answer: A. GABA transaminase
Explanation
Valproate inhibits GABA transaminase (GABA-T), the enzyme that degrades GABA to succinic semialdehyde, thereby increasing GABA concentration at synapses. It may also inhibit succinic semialdehyde dehydrogenase, further limiting GABA catabolism. Glutamic acid decarboxylase is the synthetic enzyme for GABA (valproate does not inhibit it), and MAO-B is the target of selegiline.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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