Quiz 4: DA, 5-HT, Glu, GABA, Pain Flashcards Preview

Physiology I Midterm > Quiz 4: DA, 5-HT, Glu, GABA, Pain > Flashcards

Flashcards in Quiz 4: DA, 5-HT, Glu, GABA, Pain Deck (46)
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1
Q

DA neurons are found in the

(2)

A
  • SN
    • (substanstia nigra)
  • VTA
    • (ventral tegmental area)
2
Q

Which of the following is believed to be increased in the nucleus accumbens by all drugs of abuse.

A

DA

3
Q

Most antipsychotic drugs are

A

D2-like receptor antagonists

4
Q

AADC

(5)

A
  • Is also called dopa decarboxylase
  • is required for the synthesis of DA, NE, and 5-HT (5-HT is serotonin).
  • is inhibited by carbidopa
  • converts L-DOPA to DA
  • converts 5-HTP to 5-HT

Does NOT converts DA to NE

5
Q

Parkinson’s disease is caused by the degeneration of

(3)

A
  • DA neurons in the substantia nigra
  • DA terminals in the basal ganglia
  • nigrostriatal DA neurons

Not found in:

  • DA terminals in the motor cortex
  • mesolimbic DA neurons
  • mesocortical DA neuron
  • Striatal neurons
6
Q

Which of the following is found in both serotonin and catecholamine neurons?

(4)

A
  • AADC
  • Dopa decarboxylase
  • MAO
  • VMAT
    • The vesicular monoamine transporter acts to transport monoamine neurotransmitters – such as dopamine, serotonin, norepinephrine, epinephrine, and histamine – into the vesicles, which release the neurotransmitters into synapses as chemical messages to postsynaptic neurons.
7
Q

In which of the following diseases is there reason to believe that the mesolimbic DA system is hypoactive?

A

Major depression

Notes: mesolimbic dopamine system is composed of the VTA (ventral tegumental area) and NAc (nucleus accumbens) and controls an individual’s responses to natural rewards, such as food, sex, and social interactions, and is therefore an important determinant of motivation and incentive drive.

8
Q

Which of the following are used for the treatment of the motor symptoms of Parkinson’s disease?

(3)

A
  • D2 agonists
    • Notes: act directly on dopamine receptors and mimicking the endogenous neurotransmitter.
  • MAO_B_ inhibitors
    • Notes: help to block the break down of dopamine in the brain, thus making more dopamine available and reducing some of the motor symptoms associated with PD
  • mAchR antagonists
    • Notes: muscarinic acetylcholine receptors

Are not aused for treatment of PD: MAOA inhibitors or D1 agonists

9
Q

AADC is present in

A

almost all cell types in the body

10
Q

Which of the following statements are true?

  1. D1-like receptors are Gi-coupled receptors
  2. D2-like receptors are Gi-coupled receptors
  3. DA autoreceptors are D2-like receptors.
  4. DA autoreceptors are D1-like receptors.
  5. Activation of DA autoreceptors inhibits DA neurons
A
  1. D1-like receptors are Gi-coupled receptors
  2. D2-like receptors are Gi-coupled receptors
  3. DA autoreceptors are D2-like receptors.
  4. DA autoreceptors are D1-like receptors.
  5. Activation of DA autoreceptors inhibits DA neurons
11
Q

In which of the following diseases is there reason to believe that the mesocortical DA system is hypoactive?

A

Schizophrenia

12
Q

Aripiprazole is an

(2)

A
  • antipsychotic drug
  • DA agonist
    • ​Notes: is a D2-like receptor and partial D2 agonist
13
Q

Which of the following are used for the treatment of the motor symptoms of Parkinson’s disease?

(2)

A
  • COMT inhibitors
    • Tolcapone (xBBB), Entacapone
  • AADC inhibitors
    • Given with L-Dopa
    • Do not cross BBB

ARE NOT used for treatment of motor symptoms of PD:

  • DAT inhibitors
  • SSRIs
  • Antipsychotic drugs
14
Q

Extrapyramidal Syndromes (EPS)

(2)

A
  • may be reduced by antiparkinsonian drugs
    • L-Dopa
    • DA agonists
    • MAOB inhibitors
    • Non-DA drugs
  • are side effects of antipsychotic drugs
    • ​typical antipsychotic drugs - 1st generation
    • are D2 antagonists (Chlorpromazine, haloperidol, fluphenazine)
    • also cause prolactin secretion
15
Q

Most antipsychotic drugs are

(2)

A
  • Effective in improving positive symptoms
  • Capable of increasing DA release
16
Q

Amphetamine-like psychostimulants increase the extracellular levels of

(3)

A
  • NE
  • 5-HT
  • DA

Note: Cocaine and MDMA (Ecstasy) also increase these levels of reuptake inhibitors

17
Q

The 5-HT-mediated synaptic transmission can be enhanced by the following except:

  1. Inhibition of COMT
  2. Inhibition of MAOA
  3. Inhibition of MAOB
  4. Blockade of VMAT
  5. Blockade of 5-HTT
  6. Blockade of 5-HT1A/1D autoreceptors
  7. Blockade of α1 receptors on 5-HT neurons
  8. Activation of tryptophan hydroxylase
A

The 5-HT-mediated synaptic transmission cannot be enhanced by:

  • Inhibition of COMT
  • Inhibition of MAOB
  • Blockade of VMAT
  • Blockade of α1 receptors on 5-HT neurons

The 5-HT-mediated synaptic transmission can be enhanced by:

  • Inhibition of MAOA
  • Blockade of 5-HTT
  • Blockade of 5-HT1A/1D autoreceptors
  • Activation of tryptophan hydroxylase
18
Q

Triptans are

A
  • 5-HT1B/D agonists
  • drugs for treatment of migraine
19
Q

Which of the following is found in both serotonin and catecholamine neurons?

(3)

A
  • VMAT
  • AAAT
  • MAOA

(also AADC, Dopa decarboxylase, MAO is found in both serotonin and catecholamine neurons)

20
Q

Which of the following are targets of antidepressant drugs?

A

MAOA**

(also DAT, 5-HTT, and NET are targets of antidepressant drugs)

(NOT targets: DBH, MAOB, LAT1, AAAT, TH)

21
Q

Which of the following are target of antidepressant drugs?

(3)

A
  • DAT
  • NET
  • 5-HTT

(MAOA is also a target)

NOT targets of antidepressant drugs: COMT, AADC, VMAT

22
Q

Prozac is a

(2)

A
  • antidepressant
  • 5-HT reuptake blocker

(prozac is also an SSRI)

NOT the following:

  • 5-HT antagonist
  • direct 5-HT receptor agonist
23
Q

Prozac is a

(1)

A

SSRI

(Prozac is also an antidepressant and 5-HT reuptake blocker)

Prozac is NOT the following:

  • monoamine oxidase inhibitor
  • SNRI
  • Antipsychotic drug
  • inhibitor of 5-HT synthesis
24
Q

LSD is a

(abbreviated for D-Lysergic Acid Diethylamide)

(2)

A
  • 5-HT2 agonist
    • 5-HT2A/2C agonist
  • Hallucinogen
    • other hallucinogens include amphetamine, cannabinoids, PCP, Salvinorin A, and Scopolamine
25
Q

Most 5-HT neurons in the brain are located in the

A

raphe nuclei

Note: the CNS (sleep, mood, appetite)

26
Q

Which of the following receptors requires activation by two different ligands?

A

NMDA receptor

Notes about NMDA receptor:

  • NMDA receptor is a glutamate receptor and is ionotropic.
  • Co-Agonist is Glycine
  • Long Term Potentiation
    • Voltage-dependent blockade by Mg2+
    • Activation by high frequency stimulation
    • CaM – Ca2+-Calmodulin complex
    • CaMK – CaM dependent- Kinase
27
Q

GAD (Glutamic Acid Decarboxylase) is a key enzyme required for the synthesis of

A

GABA

Notes:

Allylglycine inhibits GAD

28
Q

Benzodiazepines are useful in treating a number of brain disorders including anxiety and insomnia. The main mechanism of action of this class of drugs is to

A

increase the affinity of GABA for GABAA receptors

  • Notes:*
  • Benzodiazepines are GABA modulators*
  • examples: Z drugs (Zolpidem), anticonvulsant, hypnotic, anxiolytic
  • Benzodiazepines increase GAVA infinity (potency) while Barbiturates increase GABA efficacy*
  • examples: anticonvulsant, anesthetic
29
Q

In the brain, glutamine synthetase is primarily found in

(2)

A
  • glial cells
  • astrocytes
30
Q

Ketamine is a

  • non-competitive NMDA receptor antagonist.
  • dissociative anesthetic.
  • analgesic.
  • “Vitamin K” (street name)
  • fast acting antidepressant
  • psychotomimetic.
  • drug of abuse.
A
  • non-competitive NMDA receptor antagonist.
    • a glutamate antagonist
  • dissociative anesthetic
  • analgesic
  • Vitamin K” (street name)
  • fast acting antidepressant
  • psychotomimetic.
  • drug of abuse.

(All of the above)

31
Q

Uptake is an important mechanism to remove released neurotransmitters from the synaptic cleft. Astrocytes play a critical role in uptake of

(3)

A
  • Glycine
  • Glutamate
  • GABA
32
Q

Drugs that increase the GABA-mediated transmission tend to produce the following effects:

(4)

A
  • anxiolytic
  • anticonvulsant
  • causing drowsiness
  • physical dependence
33
Q

Glutamate is converted to GABA by

A

GAD

34
Q

Which of the following receptors are coupled to Gi protein?

(5)

A
  • α2
  • D2
  • 5-HT1A/D
  • mGluR2
  • GABAB
35
Q

Which of the following statements is TRUE?

  • Activation of GABAA receptors increases the membrane permeability to Cl-.
  • GABA is synthesized from glutamate by the enzyme GABA transaminase
  • All GABA receptors are ionotropic receptors.
  • GABAC receptors are GPCRs.
  • Most interneurons in the cortex are GABAergic, whereas most cortical projection neurons (i.e., pyramidal neurons) are glutamatergic.
A
  • Activation of GABAA receptors increases the membrane permeability to Cl-.
  • GABA is synthesized from glutamate by the enzyme GABA transaminase
  • All GABA receptors are ionotropic receptors.
  • GABAC receptors are GPCRs.
  • Most interneurons in the cortex are GABAergic, whereas most cortical projection neurons (i.e., pyramidal neurons) are glutamatergic.
36
Q

Which of the following statement is True?

  • Glycine is an obligate co-agonist at NMDA receptors
  • mGluR2/3 can function as inhibitory autoreceptors
  • Almost all neurons are glutamatergic
  • PCP is antipsychotic drug
  • PCP is a competitive NMDA receptor antagonist
  • Almost all neurons in the brain express glutamate receptors
  • NMDA receptors are G-protein coupled receptors
  • PCP is a non-competitive NMDA receptor antagonist
  • PCP is psychotomimetic
  • All glutamate receptors are ligand-gated channels
  • PCP is a NMDA receptor agonist
  • Glutamate always excites its target cells
A
  • Glycine is an obligate co-agonist at NMDA receptors
  • mGluR2/3 can function as inhibitory autoreceptors
  • Almost all neurons in the brain express glutamate receptors
  • PCP is a non-competitive NMDA receptor antagonist
  • PCP is psychotomimetic
37
Q

The major action of barbiturates is to

A

increase the efficacy of GABA, i.e., to prolong opening of Cl- channels when GABAA receptors are activated by GABA.

38
Q

Which of the following are not glutamate receptors?

  • and which ARE glutamate receptor?
A
  • Glycine receptor
  • Glutamine receptor

BELOW ARE GLUTAMATE RECEPTORS:

  • Kainate receptor
  • AMPA receptor
  • mGluR1 receptor
  • NMDA receptor
39
Q

Glutamine synthetase converts

A

glutamate to glutamine

40
Q

Which of the following is TRUE?

  • Both NSAIDs and paracetamol inhibit COX and prostaglandin synthesis
  • Morphine is a weak analgesic because it does not cross the BBB.
  • Noxious stimuli directly activate PGE2 receptors on nociceptive fibers.
  • Morphine is anti-inflammatory.
  • Paracetamol is an analgesic agent, but it is not an NSAID as it has little anti-inflammatory action.
  • TRP channels on nociceptive fibers are sensitive to high, but not low, temperatures.
A
  • Both NSAIDs and paracetamol inhibit COX and prostaglandin synthesis
  • Paracetamol is an analgesic agent, but it is not an NSAID as it has little anti-inflammatory action.
41
Q

Common causes of neuropathic pain include

A
  • chemotherapy
  • amputation
  • multiple sclerosis
  • AIDS
  • shingles
  • diabetes

(all of the above)

42
Q

All of the following have been recommended for treatment of pain except: (2 answers)

  • Question 2: Which ARE recommended for treatment of pain?
A

Are NOT recommended for pain:

  • fluoxetine
  • SSRIs

ARE recommended for pain:

  • clonidine
  • gabapentin
  • lamotrigine
  • SNRIs
  • NSAIDs
  • morphine
  • TCAs
43
Q

Morphine produces its analgesic effect by

A

stimulating opiod μ receptors

44
Q

Neuropathic pain is a result of:

A

disordered nerve function

45
Q

Which of the following statements are TRUE?

  • Acetaminophen has little anti-inflammatory effect because it does not inhibit Cox.
  • All analgesics are anti-inflammatory
  • Glucocorticoids such as cortisol are potent anti- inflammatory agents, but they are not classified as analgesics.
  • All anti-inflammatory drugs are analgesics.
  • Tylenol is not an NSAID because it is not anti-inflammatory.
  • NSAIDs are both anti-inflammatory and analgesic.
  • Paracetamol is not an NSAID because it does not inhibit Cox.
A
  • Glucocorticoids such as cortisol are potent anti- inflammatory agents, but they are not classified as analgesics.
  • Tylenol is not an NSAID because it is not anti-inflammatory
  • NSAIDs are both anti-inflammatory and analgesic
46
Q

Enkephalins, Endorphins, and Dynorphines:

  1. are ____ and ____.
  2. are released during ____
  3. bind to and activate ____
  4. produce ____
A

Enkephalins, Endorphins, and Dynorphines:

  1. are endogenous opioid peptides and are natural painkillers
  2. are released during long, continuous workouts
  3. bind to activate opioid receptors
  4. produce euphoria

Note: they do NOT bind to and inhibit opioid receptors