CHAMBERLAIN UNIVERSITY – NR 546 FINAL EXAM –
QUESTIONS AND ANSWERS | 2026/2027 LATEST UPDATE
SECTION 1: NEUROBIOLOGY AND PSYCHOPHARMACOLOGY
FOUNDATIONS
Questions 1–27
1. Which neurotransmitter network is most directly associated with the neurobiological
regulation of mood and commonly targeted by antidepressant therapy?
A) Serotonin, norepinephrine, and dopamine pathways
B) Acetylcholine, histamine, and glycine pathways
C) Glutamate, melatonin, and acetylcholine pathways
D) GABA, histamine, and orexin pathways
Correct Answer: Serotonin, norepinephrine, and dopamine pathways
Rationale: Serotonin, norepinephrine, and dopamine are central neurotransmitters involved in
mood regulation and are important targets of many antidepressant medications. Dysfunction in
these systems can contribute to depressive symptoms involving mood, motivation, cognition,
and energy. Understanding these networks helps the PMHNP connect medication mechanisms
with clinical symptom domains.
2. The mechanism of action for SSRIs involves which primary effect on the synaptic cleft?
A) Inhibition of monoamine oxidase enzyme
B) Blockade of postsynaptic dopamine receptors
C) Inhibition of serotonin reuptake transporters
D) Antagonism of NMDA glutamate receptors
Correct Answer: Inhibition of serotonin reuptake transporters
Rationale: SSRIs block the serotonin transporter (SERT), preventing reuptake of serotonin into
the presynaptic neuron, thereby increasing serotonin availability in the synaptic cleft. This
mechanism distinguishes them from MAOIs, which inhibit enzymatic breakdown, and from
antipsychotics, which block dopamine receptors.
3. The NMDA receptor antagonist ketamine is thought to exert rapid antidepressant effects
primarily through which mechanism?
A) Increased dopamine release in the nucleus accumbens
B) Enhanced GABAergic inhibition in the limbic system
C) Modulation of glutamatergic transmission and synaptic plasticity
D) Direct agonism of serotonin 5-HT2A receptors
Correct Answer: Modulation of glutamatergic transmission and synaptic plasticity
Rationale: Ketamine blocks NMDA receptors and triggers a cascade of downstream effects,
including increased BDNF release and mTOR activation, leading to enhanced synaptogenesis
,and rapid improvement in depressive symptoms. This glutamatergic mechanism represents a
novel target distinct from monoamine-based approaches.
4. The primary role of the hypothalamic-pituitary-adrenal (HPA) axis in stress response
involves secretion of which hormone?
A) Thyroxine (T4)
B) Cortisol
C) Insulin
D) Estrogen
Correct Answer: Cortisol
Rationale: The HPA axis is the body's central stress response system, culminating in the release
of cortisol from the adrenal cortex. Chronic hyperactivity of the HPA axis, with elevated cortisol
levels, is observed in many patients with major depressive disorder and is associated with
hippocampal volume loss and impaired neurogenesis.
5. Dopamine receptors are classified into D1-like and D2-like families. Which receptor is most
relevant to antipsychotic efficacy?
A) D1 receptor
B) D2 receptor
C) D3 receptor
D) D4 receptor
Correct Answer: D2 receptor
Rationale: All approved antipsychotics block D2 receptors, which is central to their efficacy in
reducing positive symptoms of psychosis. D2 receptor blockade in the mesolimbic pathway
reduces dopaminergic hyperactivity, while blockade in the nigrostriatal pathway may lead to
extrapyramidal side effects.
6. Serotonin 5-HT2A receptor antagonism is associated with which clinical effect when added
to D2 receptor blockade?
A) Increased risk of extrapyramidal symptoms
B) Reduced efficacy in treating negative symptoms
C) Decreased risk of hyperprolactinemia and improved negative symptoms
D) Increased sedative effects through histamine potentiation
Correct Answer: Decreased risk of hyperprolactinemia and improved negative symptoms
Rationale: Atypical antipsychotics combine D2 antagonism with 5-HT2A antagonism. This
combination is associated with a lower incidence of extrapyramidal side effects, reduced
prolactin elevation, and modest improvement in negative and cognitive symptoms compared to
typical antipsychotics.
7. The enzyme catechol-O-methyltransferase (COMT) is responsible for which metabolic
function?
A) Breakdown of acetylcholine
,B) Synthesis of melatonin from serotonin
C) Degradation of dopamine and norepinephrine
D) Conversion of tyrosine to DOPA
Correct Answer: Degradation of dopamine and norepinephrine
Rationale: COMT is an enzyme that metabolizes catecholamines, including dopamine and
norepinephrine, by adding a methyl group. COMT inhibitors, such as tolcapone and entacapone,
are used in Parkinson's disease and have been investigated for cognitive enhancement in
psychiatric disorders.
8. Which of the following is an example of a receptor that is primarily inhibitory and mediates
fast synaptic transmission in the brain?
A) NMDA receptor
B) AMPA receptor
C) GABA-A receptor
D) Nicotinic acetylcholine receptor
Correct Answer: GABA-A receptor
Rationale: GABA-A receptors are ligand-gated chloride channels that mediate fast inhibitory
neurotransmission in the brain. When GABA binds, chloride ions enter the neuron,
hyperpolarizing it and reducing neuronal excitability. This mechanism is the target of
benzodiazepines and barbiturates.
9. Brain-derived neurotrophic factor (BDNF) is critically involved in which neurobiological
process related to depression?
A) Neurogenesis and synaptic plasticity
B) Dopamine synthesis in the ventral tegmental area
C) Myelination of cortical neurons
D) Reuptake of serotonin at the synaptic cleft
Correct Answer: Neurogenesis and synaptic plasticity
Rationale: BDNF promotes the survival, growth, and differentiation of neurons and plays a key
role in synaptic plasticity and neurogenesis in the hippocampus. Decreased BDNF levels are
associated with depressive disorders, and antidepressants may work partly by increasing BDNF
expression.
10. The blood-brain barrier (BBB) is primarily composed of which cellular structure?
A) Astrocyte end-feet surrounding capillary endothelial cells
B) Neuronal cell bodies and dendrites
C) Oligodendrocyte myelin sheaths
D) Microglial phagocytic cells
Correct Answer: Astrocyte end-feet surrounding capillary endothelial cells
Rationale: The BBB is formed by tight junctions between endothelial cells of brain capillaries,
reinforced by astrocyte end-feet that provide structural support and regulate transport. This
, barrier restricts the passage of many drugs, requiring agents with adequate lipophilicity to enter
the central nervous system.
11. Which cytochrome P450 enzyme is responsible for metabolizing the largest percentage of
commonly prescribed psychotropic medications?
A) CYP2D6
B) CYP3A4
C) CYP2C9
D) CYP1A2
Correct Answer: CYP3A4
Rationale: CYP3A4 is the most abundant cytochrome P450 enzyme in the liver and is involved in
the metabolism of approximately 50% of all medications, including many antidepressants,
antipsychotics, and benzodiazepines. Its activity is subject to significant genetic variation and
drug interactions.
12. A patient prescribed fluoxetine (Prozac) develops insomnia and agitation. These side
effects are most directly related to which pharmacological action?
A) Antagonism of histamine H1 receptors
B) Increased serotonergic tone, particularly 5-HT2A activation
C) Blockade of muscarinic acetylcholine receptors
D) Inhibition of norepinephrine reuptake
Correct Answer: Increased serotonergic tone, particularly 5-HT2A activation
Rationale: Initial increased serotonergic activity can stimulate 5-HT2A receptors, leading to
insomnia, agitation, and anxiety. Histamine antagonism would produce sedation, muscarinic
blockade causes anticholinergic effects, and while some SSRIs also affect norepinephrine (e.g.,
fluoxetine at higher doses), the primary activating side effects are serotonergic.
13. Which of the following best describes the mechanism of action of bupropion?
A) Selective serotonin reuptake inhibition
B) Serotonin and norepinephrine reuptake inhibition
C) Dopamine and norepinephrine reuptake inhibition
D) Serotonin receptor agonism and NMDA antagonism
Correct Answer: Dopamine and norepinephrine reuptake inhibition
Rationale: Bupropion is a dopamine and norepinephrine reuptake inhibitor (DNRI). It does not
significantly affect serotonin, which accounts for its lack of serotonergic side effects (e.g., weight
gain, sexual dysfunction) and its efficacy in depression with atypical features or fatigue.
14. The neurobiological mechanism of lithium's mood-stabilizing effects is thought to involve
which primary pathway?
A) Enhancement of GABA-A receptor function
B) Inhibition of glycogen synthase kinase-3 beta (GSK-3β) and inositol monophosphatase
C) Blockade of NMDA receptors and increased glutamate release
QUESTIONS AND ANSWERS | 2026/2027 LATEST UPDATE
SECTION 1: NEUROBIOLOGY AND PSYCHOPHARMACOLOGY
FOUNDATIONS
Questions 1–27
1. Which neurotransmitter network is most directly associated with the neurobiological
regulation of mood and commonly targeted by antidepressant therapy?
A) Serotonin, norepinephrine, and dopamine pathways
B) Acetylcholine, histamine, and glycine pathways
C) Glutamate, melatonin, and acetylcholine pathways
D) GABA, histamine, and orexin pathways
Correct Answer: Serotonin, norepinephrine, and dopamine pathways
Rationale: Serotonin, norepinephrine, and dopamine are central neurotransmitters involved in
mood regulation and are important targets of many antidepressant medications. Dysfunction in
these systems can contribute to depressive symptoms involving mood, motivation, cognition,
and energy. Understanding these networks helps the PMHNP connect medication mechanisms
with clinical symptom domains.
2. The mechanism of action for SSRIs involves which primary effect on the synaptic cleft?
A) Inhibition of monoamine oxidase enzyme
B) Blockade of postsynaptic dopamine receptors
C) Inhibition of serotonin reuptake transporters
D) Antagonism of NMDA glutamate receptors
Correct Answer: Inhibition of serotonin reuptake transporters
Rationale: SSRIs block the serotonin transporter (SERT), preventing reuptake of serotonin into
the presynaptic neuron, thereby increasing serotonin availability in the synaptic cleft. This
mechanism distinguishes them from MAOIs, which inhibit enzymatic breakdown, and from
antipsychotics, which block dopamine receptors.
3. The NMDA receptor antagonist ketamine is thought to exert rapid antidepressant effects
primarily through which mechanism?
A) Increased dopamine release in the nucleus accumbens
B) Enhanced GABAergic inhibition in the limbic system
C) Modulation of glutamatergic transmission and synaptic plasticity
D) Direct agonism of serotonin 5-HT2A receptors
Correct Answer: Modulation of glutamatergic transmission and synaptic plasticity
Rationale: Ketamine blocks NMDA receptors and triggers a cascade of downstream effects,
including increased BDNF release and mTOR activation, leading to enhanced synaptogenesis
,and rapid improvement in depressive symptoms. This glutamatergic mechanism represents a
novel target distinct from monoamine-based approaches.
4. The primary role of the hypothalamic-pituitary-adrenal (HPA) axis in stress response
involves secretion of which hormone?
A) Thyroxine (T4)
B) Cortisol
C) Insulin
D) Estrogen
Correct Answer: Cortisol
Rationale: The HPA axis is the body's central stress response system, culminating in the release
of cortisol from the adrenal cortex. Chronic hyperactivity of the HPA axis, with elevated cortisol
levels, is observed in many patients with major depressive disorder and is associated with
hippocampal volume loss and impaired neurogenesis.
5. Dopamine receptors are classified into D1-like and D2-like families. Which receptor is most
relevant to antipsychotic efficacy?
A) D1 receptor
B) D2 receptor
C) D3 receptor
D) D4 receptor
Correct Answer: D2 receptor
Rationale: All approved antipsychotics block D2 receptors, which is central to their efficacy in
reducing positive symptoms of psychosis. D2 receptor blockade in the mesolimbic pathway
reduces dopaminergic hyperactivity, while blockade in the nigrostriatal pathway may lead to
extrapyramidal side effects.
6. Serotonin 5-HT2A receptor antagonism is associated with which clinical effect when added
to D2 receptor blockade?
A) Increased risk of extrapyramidal symptoms
B) Reduced efficacy in treating negative symptoms
C) Decreased risk of hyperprolactinemia and improved negative symptoms
D) Increased sedative effects through histamine potentiation
Correct Answer: Decreased risk of hyperprolactinemia and improved negative symptoms
Rationale: Atypical antipsychotics combine D2 antagonism with 5-HT2A antagonism. This
combination is associated with a lower incidence of extrapyramidal side effects, reduced
prolactin elevation, and modest improvement in negative and cognitive symptoms compared to
typical antipsychotics.
7. The enzyme catechol-O-methyltransferase (COMT) is responsible for which metabolic
function?
A) Breakdown of acetylcholine
,B) Synthesis of melatonin from serotonin
C) Degradation of dopamine and norepinephrine
D) Conversion of tyrosine to DOPA
Correct Answer: Degradation of dopamine and norepinephrine
Rationale: COMT is an enzyme that metabolizes catecholamines, including dopamine and
norepinephrine, by adding a methyl group. COMT inhibitors, such as tolcapone and entacapone,
are used in Parkinson's disease and have been investigated for cognitive enhancement in
psychiatric disorders.
8. Which of the following is an example of a receptor that is primarily inhibitory and mediates
fast synaptic transmission in the brain?
A) NMDA receptor
B) AMPA receptor
C) GABA-A receptor
D) Nicotinic acetylcholine receptor
Correct Answer: GABA-A receptor
Rationale: GABA-A receptors are ligand-gated chloride channels that mediate fast inhibitory
neurotransmission in the brain. When GABA binds, chloride ions enter the neuron,
hyperpolarizing it and reducing neuronal excitability. This mechanism is the target of
benzodiazepines and barbiturates.
9. Brain-derived neurotrophic factor (BDNF) is critically involved in which neurobiological
process related to depression?
A) Neurogenesis and synaptic plasticity
B) Dopamine synthesis in the ventral tegmental area
C) Myelination of cortical neurons
D) Reuptake of serotonin at the synaptic cleft
Correct Answer: Neurogenesis and synaptic plasticity
Rationale: BDNF promotes the survival, growth, and differentiation of neurons and plays a key
role in synaptic plasticity and neurogenesis in the hippocampus. Decreased BDNF levels are
associated with depressive disorders, and antidepressants may work partly by increasing BDNF
expression.
10. The blood-brain barrier (BBB) is primarily composed of which cellular structure?
A) Astrocyte end-feet surrounding capillary endothelial cells
B) Neuronal cell bodies and dendrites
C) Oligodendrocyte myelin sheaths
D) Microglial phagocytic cells
Correct Answer: Astrocyte end-feet surrounding capillary endothelial cells
Rationale: The BBB is formed by tight junctions between endothelial cells of brain capillaries,
reinforced by astrocyte end-feet that provide structural support and regulate transport. This
, barrier restricts the passage of many drugs, requiring agents with adequate lipophilicity to enter
the central nervous system.
11. Which cytochrome P450 enzyme is responsible for metabolizing the largest percentage of
commonly prescribed psychotropic medications?
A) CYP2D6
B) CYP3A4
C) CYP2C9
D) CYP1A2
Correct Answer: CYP3A4
Rationale: CYP3A4 is the most abundant cytochrome P450 enzyme in the liver and is involved in
the metabolism of approximately 50% of all medications, including many antidepressants,
antipsychotics, and benzodiazepines. Its activity is subject to significant genetic variation and
drug interactions.
12. A patient prescribed fluoxetine (Prozac) develops insomnia and agitation. These side
effects are most directly related to which pharmacological action?
A) Antagonism of histamine H1 receptors
B) Increased serotonergic tone, particularly 5-HT2A activation
C) Blockade of muscarinic acetylcholine receptors
D) Inhibition of norepinephrine reuptake
Correct Answer: Increased serotonergic tone, particularly 5-HT2A activation
Rationale: Initial increased serotonergic activity can stimulate 5-HT2A receptors, leading to
insomnia, agitation, and anxiety. Histamine antagonism would produce sedation, muscarinic
blockade causes anticholinergic effects, and while some SSRIs also affect norepinephrine (e.g.,
fluoxetine at higher doses), the primary activating side effects are serotonergic.
13. Which of the following best describes the mechanism of action of bupropion?
A) Selective serotonin reuptake inhibition
B) Serotonin and norepinephrine reuptake inhibition
C) Dopamine and norepinephrine reuptake inhibition
D) Serotonin receptor agonism and NMDA antagonism
Correct Answer: Dopamine and norepinephrine reuptake inhibition
Rationale: Bupropion is a dopamine and norepinephrine reuptake inhibitor (DNRI). It does not
significantly affect serotonin, which accounts for its lack of serotonergic side effects (e.g., weight
gain, sexual dysfunction) and its efficacy in depression with atypical features or fatigue.
14. The neurobiological mechanism of lithium's mood-stabilizing effects is thought to involve
which primary pathway?
A) Enhancement of GABA-A receptor function
B) Inhibition of glycogen synthase kinase-3 beta (GSK-3β) and inositol monophosphatase
C) Blockade of NMDA receptors and increased glutamate release
