Stahl's Essential Psychopharmacology
Neuroscientific Basis and Practical Applications
5th Edition
Author(s)Stephen M. Stahl
TEST BANK
Item 1
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A patient begins a medication that blocks
vesicular monoamine transporter 2 (VMAT2). Which neural
process is most directly impaired by VMAT2 inhibition?
A. Presynaptic synthesis of monoamines from tyrosine
B. Uptake of monoamines from the synaptic cleft into the
presynaptic terminal
C. Packaging of monoamines into synaptic vesicles for release
D. Postsynaptic monoamine receptor activation
Correct Answer: C
Rationale — correct: VMAT2 transports cytosolic monoamines
into synaptic vesicles; inhibition prevents vesicular packaging
and reduces transmitter release. This mechanism is described in
Stahl’s explanation of presynaptic handling of
,neurotransmitters.
Rationale — A: Synthesis from precursors (e.g., tyrosine →
dopamine) occurs enzymatically in the cytosol and is upstream
of vesicular packaging; VMAT2 does not catalyze synthesis.
Rationale — B: Reuptake from the cleft is mediated by plasma-
membrane transporters (e.g., DAT, SERT), not VMAT2.
Rationale — D: Postsynaptic receptor activation is downstream
of release; VMAT2 blockade reduces release but does not
directly block receptors.
Teaching Point: VMAT2 loads cytosolic monoamines into
vesicles for synaptic release.
Citation: Stahl SM. Stahl’s Essential Psychopharmacology, 5th
ed — Ch. 1, Chemical Neurotransmission (pp. 1–28).
Item 2
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A psychiatrist reviews a patient’s lab report
showing markedly reduced CYP-mediated metabolism of a
psychotropic. Which presynaptic or synaptic process described
in Stahl is least affected by hepatic CYP variation?
A. Concentration of circulating prodrugs available to cross the
blood–brain barrier
B. Synaptic reuptake via plasma membrane transporters (e.g.,
SERT, NET)
C. Presynaptic vesicular packaging of neurotransmitter
,D. Postsynaptic receptor density regulated by chronic drug
exposure
Correct Answer: B
Rationale — correct: Synaptic reuptake transporters are
membrane proteins whose acute function is not directly altered
by hepatic CYP activity; CYP impacts systemic drug levels, not
intrinsic transporter kinetics.
Rationale — A: Hepatic CYPs determine conversion of prodrugs
to active compounds and influence their brain availability.
Rationale — C: VMATs and vesicular packaging are presynaptic
cellular processes unaffected by hepatic enzyme activity per se,
but transporter function remains cellular (C is plausible but B is
the least connected to hepatic CYP).
Rationale — D: Receptor density is influenced by chronic drug
exposure and systemic drug concentrations; hepatic
metabolism impacts brain exposure and thus can alter
regulation over time.
Teaching Point: Hepatic CYPs change systemic drug levels;
synaptic transporter function is intrinsic to neurons.
Citation: Stahl SM. Stahl’s Essential Psychopharmacology, 5th
ed — Ch. 1, Chemical Neurotransmission (pp. 1–28).
Item 3
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A resident asks why agonist-induced receptor
, internalization can change drug responsiveness. According to
Stahl’s account of receptor regulation, what is the primary
consequence of prolonged agonist exposure?
A. Immediate increase in receptor gene transcription producing
more receptors
B. Phosphorylation and internalization leading to
downregulation and reduced responsiveness
C. Irreversible mutation of the receptor protein
D. Increased presynaptic neurotransmitter release to
compensate
Correct Answer: B
Rationale — correct: Prolonged agonist exposure leads to
receptor phosphorylation, arrestin binding, and internalization
— cellular downregulation — reducing postsynaptic
responsiveness, as explained in Stahl’s section on up/down-
regulation.
Rationale — A: Some compensatory transcriptional changes
occur, but immediate consequence is
phosphorylation/internalization rather than rapid increased
transcription.
Rationale — C: Agonist exposure does not cause receptor
mutation.
Rationale — D: Increased presynaptic release is not the primary
cellular mechanism of postsynaptic receptor downregulation.
Teaching Point: Prolonged agonism commonly triggers receptor
phosphorylation and internalization.
Neuroscientific Basis and Practical Applications
5th Edition
Author(s)Stephen M. Stahl
TEST BANK
Item 1
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A patient begins a medication that blocks
vesicular monoamine transporter 2 (VMAT2). Which neural
process is most directly impaired by VMAT2 inhibition?
A. Presynaptic synthesis of monoamines from tyrosine
B. Uptake of monoamines from the synaptic cleft into the
presynaptic terminal
C. Packaging of monoamines into synaptic vesicles for release
D. Postsynaptic monoamine receptor activation
Correct Answer: C
Rationale — correct: VMAT2 transports cytosolic monoamines
into synaptic vesicles; inhibition prevents vesicular packaging
and reduces transmitter release. This mechanism is described in
Stahl’s explanation of presynaptic handling of
,neurotransmitters.
Rationale — A: Synthesis from precursors (e.g., tyrosine →
dopamine) occurs enzymatically in the cytosol and is upstream
of vesicular packaging; VMAT2 does not catalyze synthesis.
Rationale — B: Reuptake from the cleft is mediated by plasma-
membrane transporters (e.g., DAT, SERT), not VMAT2.
Rationale — D: Postsynaptic receptor activation is downstream
of release; VMAT2 blockade reduces release but does not
directly block receptors.
Teaching Point: VMAT2 loads cytosolic monoamines into
vesicles for synaptic release.
Citation: Stahl SM. Stahl’s Essential Psychopharmacology, 5th
ed — Ch. 1, Chemical Neurotransmission (pp. 1–28).
Item 2
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A psychiatrist reviews a patient’s lab report
showing markedly reduced CYP-mediated metabolism of a
psychotropic. Which presynaptic or synaptic process described
in Stahl is least affected by hepatic CYP variation?
A. Concentration of circulating prodrugs available to cross the
blood–brain barrier
B. Synaptic reuptake via plasma membrane transporters (e.g.,
SERT, NET)
C. Presynaptic vesicular packaging of neurotransmitter
,D. Postsynaptic receptor density regulated by chronic drug
exposure
Correct Answer: B
Rationale — correct: Synaptic reuptake transporters are
membrane proteins whose acute function is not directly altered
by hepatic CYP activity; CYP impacts systemic drug levels, not
intrinsic transporter kinetics.
Rationale — A: Hepatic CYPs determine conversion of prodrugs
to active compounds and influence their brain availability.
Rationale — C: VMATs and vesicular packaging are presynaptic
cellular processes unaffected by hepatic enzyme activity per se,
but transporter function remains cellular (C is plausible but B is
the least connected to hepatic CYP).
Rationale — D: Receptor density is influenced by chronic drug
exposure and systemic drug concentrations; hepatic
metabolism impacts brain exposure and thus can alter
regulation over time.
Teaching Point: Hepatic CYPs change systemic drug levels;
synaptic transporter function is intrinsic to neurons.
Citation: Stahl SM. Stahl’s Essential Psychopharmacology, 5th
ed — Ch. 1, Chemical Neurotransmission (pp. 1–28).
Item 3
Reference: Ch. 1 — Chemical Neurotransmission (pp. 1–28)
Question Stem: A resident asks why agonist-induced receptor
, internalization can change drug responsiveness. According to
Stahl’s account of receptor regulation, what is the primary
consequence of prolonged agonist exposure?
A. Immediate increase in receptor gene transcription producing
more receptors
B. Phosphorylation and internalization leading to
downregulation and reduced responsiveness
C. Irreversible mutation of the receptor protein
D. Increased presynaptic neurotransmitter release to
compensate
Correct Answer: B
Rationale — correct: Prolonged agonist exposure leads to
receptor phosphorylation, arrestin binding, and internalization
— cellular downregulation — reducing postsynaptic
responsiveness, as explained in Stahl’s section on up/down-
regulation.
Rationale — A: Some compensatory transcriptional changes
occur, but immediate consequence is
phosphorylation/internalization rather than rapid increased
transcription.
Rationale — C: Agonist exposure does not cause receptor
mutation.
Rationale — D: Increased presynaptic release is not the primary
cellular mechanism of postsynaptic receptor downregulation.
Teaching Point: Prolonged agonism commonly triggers receptor
phosphorylation and internalization.
