NSG552: Psychopharmacology Exam 1 Actual Exam
2026/2027 – Complete Exam-Style Questions with Detailed
Rationales | 100% Verified | Pass Guaranteed – A+ Graded
SECTION 1: Neurotransmitter Systems & Receptor Pharmacology (Q1-Q20)
Q1: Which neurotransmitter is synthesized from the amino acid tryptophan via the
rate-limiting enzyme tryptophan hydroxylase?
A. Dopamine
B. Serotonin [CORRECT]
C. Norepinephrine
D. GABA
Correct Answer: B
Rationale: Serotonin (5-HT) is synthesized from tryptophan through tryptophan
hydroxylase (rate-limiting) and aromatic L-amino acid decarboxylase. Dopamine and
norepinephrine are synthesized from tyrosine via tyrosine hydroxylase. GABA is
synthesized from glutamate via glutamic acid decarboxylase. [100% VERIFIED]
Q2: In the dopaminergic pathway, which enzyme converts dopamine to norepinephrine?
A. Monoamine oxidase (MAO)
B. Dopamine β-hydroxylase [CORRECT]
C. Catechol-O-methyltransferase (COMT)
D. Tyrosine hydroxylase
Correct Answer: B
Rationale: Dopamine β-hydroxylase (DBH) converts dopamine to norepinephrine within
synaptic vesicles. MAO degrades monoamines intracellularly; COMT methylates
catecholamines extracellularly; tyrosine hydroxylase converts tyrosine to L-DOPA
(rate-limiting step for catecholamine synthesis). [100% VERIFIED]
,Q3: Which receptor subtype is primarily responsible for the therapeutic antipsychotic
effect of typical antipsychotics?
A. D1 receptor
B. D2 receptor [CORRECT]
C. D3 receptor
D. D4 receptor
Correct Answer: B
Rationale: Blockade of D2 receptors in the mesolimbic pathway correlates with
antipsychotic efficacy. The D2 receptor hypothesis states that hyperactivity of D2
receptors contributes to positive symptoms of schizophrenia. D1 modulation is more
relevant for cognition; D3 and D4 have limited clinical significance for typical
antipsychotic efficacy. [100% VERIFIED]
Q4: Which GABA-A receptor subunit is the primary target of benzodiazepines, enhancing
chloride ion influx?
A. α subunit
B. β subunit
C. γ subunit (specifically γ2 containing the benzodiazepine binding site) [CORRECT]
D. δ subunit
Correct Answer: C
Rationale: Benzodiazepines bind to the interface between α and γ2 subunits of the
GABA-A receptor, allosterically enhancing GABA-mediated chloride conductance. The α
subunit determines benzodiazepine subtype selectivity; β subunits bind GABA; δ
subunits are involved in extrasynaptic tonic inhibition, not benzodiazepine modulation.
[100% VERIFIED]
Q5: Which serotonin receptor subtype is primarily responsible for the hallucinogenic
effects of psychedelic substances?
A. 5-HT1A
B. 5-HT2A [CORRECT]
C. 5-HT3
,D. 5-HT4
Correct Answer: B
Rationale: 5-HT2A receptor agonism in the prefrontal cortex is the primary mechanism
for hallucinogenic effects. Atypical antipsychotics antagonize 5-HT2A to improve
negative symptoms and reduce EPS. 5-HT1A is targeted by buspirone and vilazodone;
5-HT3 is targeted by antiemetics; 5-HT4 affects GI motility. [100% VERIFIED]
Q6: The NMDA receptor requires co-agonist binding of glutamate and which other
molecule for channel opening?
A. GABA
B. Glycine [CORRECT]
C. Serotonin
D. Acetylcholine
Correct Answer: B
Rationale: NMDA receptors require both glutamate and glycine (or D-serine) as
co-agonists for channel opening, along with membrane depolarization to relieve Mg2+
block. GABA is inhibitory; serotonin and acetylcholine are unrelated to NMDA receptor
gating. This co-agonist requirement is a key pharmacologic target. [100% VERIFIED]
Q7: Which transporter is responsible for reuptake of serotonin from the synaptic cleft
into the presynaptic neuron?
A. DAT (dopamine transporter)
B. NET (norepinephrine transporter)
C. SERT (serotonin transporter) [CORRECT]
D. VMAT2 (vesicular monoamine transporter 2)
Correct Answer: C
Rationale: SERT (SLC6A4) is the specific transporter for serotonin reuptake and is the
primary target of SSRIs. DAT handles dopamine reuptake (target of stimulants); NET
, handles norepinephrine; VMAT2 packages monoamines into synaptic vesicles (target of
reserpine and tetrabenazine). [100% VERIFIED]
Q8: Which enzyme is responsible for the metabolism of serotonin to
5-hydroxyindoleacetic acid (5-HIAA)?
A. COMT
B. MAO-A [CORRECT]
C. MAO-B
D. Cytochrome P450 2D6
Correct Answer: B
Rationale: MAO-A preferentially metabolizes serotonin and norepinephrine; MAO-B
preferentially metabolizes dopamine and phenethylamine. COMT methylates
catecholamines extracellularly; CYP2D6 metabolizes many psychotropic drugs but not
serotonin itself. MAO-A inhibition is the mechanism of MAOI antidepressants. [100%
VERIFIED]
Q9: Which acetylcholine receptor subtype is a ligand-gated ion channel (ionotropic)
found at the neuromuscular junction?
A. Muscarinic M1 receptor
B. Nicotinic receptor (Nn)
C. Nicotinic receptor (Nm) [CORRECT]
D. Muscarinic M3 receptor
Correct Answer: C
Rationale: Nicotinic receptors at the neuromuscular junction are designated Nm
(muscle type), composed of α1, β1, γ/ε, and δ subunits. Nn (neuronal type) is found in
autonomic ganglia and CNS. Muscarinic receptors (M1-M5) are GPCRs, not ion
channels. [100% VERIFIED]
2026/2027 – Complete Exam-Style Questions with Detailed
Rationales | 100% Verified | Pass Guaranteed – A+ Graded
SECTION 1: Neurotransmitter Systems & Receptor Pharmacology (Q1-Q20)
Q1: Which neurotransmitter is synthesized from the amino acid tryptophan via the
rate-limiting enzyme tryptophan hydroxylase?
A. Dopamine
B. Serotonin [CORRECT]
C. Norepinephrine
D. GABA
Correct Answer: B
Rationale: Serotonin (5-HT) is synthesized from tryptophan through tryptophan
hydroxylase (rate-limiting) and aromatic L-amino acid decarboxylase. Dopamine and
norepinephrine are synthesized from tyrosine via tyrosine hydroxylase. GABA is
synthesized from glutamate via glutamic acid decarboxylase. [100% VERIFIED]
Q2: In the dopaminergic pathway, which enzyme converts dopamine to norepinephrine?
A. Monoamine oxidase (MAO)
B. Dopamine β-hydroxylase [CORRECT]
C. Catechol-O-methyltransferase (COMT)
D. Tyrosine hydroxylase
Correct Answer: B
Rationale: Dopamine β-hydroxylase (DBH) converts dopamine to norepinephrine within
synaptic vesicles. MAO degrades monoamines intracellularly; COMT methylates
catecholamines extracellularly; tyrosine hydroxylase converts tyrosine to L-DOPA
(rate-limiting step for catecholamine synthesis). [100% VERIFIED]
,Q3: Which receptor subtype is primarily responsible for the therapeutic antipsychotic
effect of typical antipsychotics?
A. D1 receptor
B. D2 receptor [CORRECT]
C. D3 receptor
D. D4 receptor
Correct Answer: B
Rationale: Blockade of D2 receptors in the mesolimbic pathway correlates with
antipsychotic efficacy. The D2 receptor hypothesis states that hyperactivity of D2
receptors contributes to positive symptoms of schizophrenia. D1 modulation is more
relevant for cognition; D3 and D4 have limited clinical significance for typical
antipsychotic efficacy. [100% VERIFIED]
Q4: Which GABA-A receptor subunit is the primary target of benzodiazepines, enhancing
chloride ion influx?
A. α subunit
B. β subunit
C. γ subunit (specifically γ2 containing the benzodiazepine binding site) [CORRECT]
D. δ subunit
Correct Answer: C
Rationale: Benzodiazepines bind to the interface between α and γ2 subunits of the
GABA-A receptor, allosterically enhancing GABA-mediated chloride conductance. The α
subunit determines benzodiazepine subtype selectivity; β subunits bind GABA; δ
subunits are involved in extrasynaptic tonic inhibition, not benzodiazepine modulation.
[100% VERIFIED]
Q5: Which serotonin receptor subtype is primarily responsible for the hallucinogenic
effects of psychedelic substances?
A. 5-HT1A
B. 5-HT2A [CORRECT]
C. 5-HT3
,D. 5-HT4
Correct Answer: B
Rationale: 5-HT2A receptor agonism in the prefrontal cortex is the primary mechanism
for hallucinogenic effects. Atypical antipsychotics antagonize 5-HT2A to improve
negative symptoms and reduce EPS. 5-HT1A is targeted by buspirone and vilazodone;
5-HT3 is targeted by antiemetics; 5-HT4 affects GI motility. [100% VERIFIED]
Q6: The NMDA receptor requires co-agonist binding of glutamate and which other
molecule for channel opening?
A. GABA
B. Glycine [CORRECT]
C. Serotonin
D. Acetylcholine
Correct Answer: B
Rationale: NMDA receptors require both glutamate and glycine (or D-serine) as
co-agonists for channel opening, along with membrane depolarization to relieve Mg2+
block. GABA is inhibitory; serotonin and acetylcholine are unrelated to NMDA receptor
gating. This co-agonist requirement is a key pharmacologic target. [100% VERIFIED]
Q7: Which transporter is responsible for reuptake of serotonin from the synaptic cleft
into the presynaptic neuron?
A. DAT (dopamine transporter)
B. NET (norepinephrine transporter)
C. SERT (serotonin transporter) [CORRECT]
D. VMAT2 (vesicular monoamine transporter 2)
Correct Answer: C
Rationale: SERT (SLC6A4) is the specific transporter for serotonin reuptake and is the
primary target of SSRIs. DAT handles dopamine reuptake (target of stimulants); NET
, handles norepinephrine; VMAT2 packages monoamines into synaptic vesicles (target of
reserpine and tetrabenazine). [100% VERIFIED]
Q8: Which enzyme is responsible for the metabolism of serotonin to
5-hydroxyindoleacetic acid (5-HIAA)?
A. COMT
B. MAO-A [CORRECT]
C. MAO-B
D. Cytochrome P450 2D6
Correct Answer: B
Rationale: MAO-A preferentially metabolizes serotonin and norepinephrine; MAO-B
preferentially metabolizes dopamine and phenethylamine. COMT methylates
catecholamines extracellularly; CYP2D6 metabolizes many psychotropic drugs but not
serotonin itself. MAO-A inhibition is the mechanism of MAOI antidepressants. [100%
VERIFIED]
Q9: Which acetylcholine receptor subtype is a ligand-gated ion channel (ionotropic)
found at the neuromuscular junction?
A. Muscarinic M1 receptor
B. Nicotinic receptor (Nn)
C. Nicotinic receptor (Nm) [CORRECT]
D. Muscarinic M3 receptor
Correct Answer: C
Rationale: Nicotinic receptors at the neuromuscular junction are designated Nm
(muscle type), composed of α1, β1, γ/ε, and δ subunits. Nn (neuronal type) is found in
autonomic ganglia and CNS. Muscarinic receptors (M1-M5) are GPCRs, not ion
channels. [100% VERIFIED]
