Neurotransmitter Systems

Question 1

What uses slow axonal transport?

Answer 1

Cytostructural components (mitochondria) or ion channels/receptors

Question 2

What can travel retrograde back to the soma from the synapse?

Answer 2

• neurotrophic substances
• used vesicles and intracellular organelles
• Also some viruses (rabies)

Question 3

What uses fast axonal transport?

Answer 3

Neurotransmitter vesicles from the soma to the synapse

Question 4

Name the 3 catecholamine neurotransmitters

Answer 4

Norepiniphrine, epinephrine, and dopamine

Question 5

What are the catecholamines synthesized from

Answer 5

tyrosine

Question 6

what is the enzyme for tyrosine to L-DOPA?

Answer 6

tyrosine hydroxylase

Question 7

where is dopamine beta hydroxylase located?

Answer 7

intracellular vesicular membrane

Question 8

Where is norepinephrine synthesized?

Answer 8

within vesicles

Question 9

What enzyme coverts norepinephrine to epinephrine and where does this occur?

Answer 9

PNMT; outside of the vesicle

Question 10

Where is norepinephrine found in the central nervous system?

Answer 10

locus ceruleus

Question 11

What does norepinephrine play a crucial role in?

Answer 11

waking us up; awareness

Question 12

What are the proteins that move the catecholamines into vesicles?

Answer 12

VMATs

Question 13

Where is VMAT1 found and what does it do?

Answer 13

adrenal medulla; moves both dopamine into the vesicle for its conversion to norepinephrine AND then the epinephrine that was created in the cytoplasm back into the vesicles

Question 14

Where is VMAT2 found?

Answer 14

any neuron that releases the monoamines

Question 15

What does VMAT2 do?

Answer 15

1) moves any monoamines into vesicles for either synthesis of norepinephrine or storage prior to release.
2) it can move toxins into the vesicles to protect the neurons from the toxin

Question 16

What drug are VMAT 1 and 2 sensitive to and what is this drug used for?

Answer 16

Reserpine; hypertension

Question 17

Which dopamine receptors are Gs coupled?

Answer 17

D1 and D5 (D1-like)

Question 18

which dopamine receptors are Gi coupled?

Answer 18

D2, D3, and D4 (D2-like)

Question 19

D1 receptor action

Answer 19

voluntary motion

Question 20

D2 receptor action

Answer 20

inhibits motion

Question 21

D3 receptor action

Answer 21

pleasure/reward system

Question 22

What are the 2 ways to remove catecholamines from the synaptic cleft?

Answer 22

Reuptake and enzymatic destruction

Question 23

What are the 2 enzymes used for enzymatic destruction of the catecholamines in the synaptic cleft?

Answer 23

MAO and COMT

Question 24

Serotonin is synthesized from what amino acid?

Answer 24

tryptophan

Question 25

What is the large cluster of neurons that use serotonin as their neurotransmitter?

Answer 25

midline raphe nuclei

Question 26

serotonin plays a role in controlling what and disruptions in transmission are associated with what?

Answer 26

attention and mood; depression

Question 27

How many different 5-HT (serotonin) receptors are there?

Answer 27

SEVEN

Question 28

How is serotonin removed from the synaptic cleft?

Answer 28

metabolized by MAO AFTER REUPTAKE

Question 29

What amino acid is histamine derived from?

Answer 29

histidine

Question 30

Where is histamine found in the central nervous system?

Answer 30

Posterior hypothalamus in the tuberomammillary body

Question 31

What is histamine most directly associated with?

Answer 31

wakefulness

Question 32

What enzyme degrades histamine from the synaptic cleft?

Answer 32

diamine oxidase

Question 33

Enzyme that takes acetate CoA and choline and makes ACh?

Answer 33

Choline acetyltransferase

Question 34

What transports ACh into the vesicle?

Answer 34

VAchT

Question 35

What breaks down Ach?

Answer 35

Acetylcholinesterase

Question 36

When Ach is broken down in the cleft into acetate and choline, which one is recycled by the cell and which one diffuses away?

Answer 36

Choline is recycled; Acetate diffuses

Question 37

2 receptor types for Ach

Answer 37

muscarinic and nictotinic

Question 38

What block the muscarinic receptor?

Answer 38

Atropine

Question 39

M1 mechanism

Answer 39

increase IP3, DAG lead to increase in intracellular Ca+2

Question 40

M2 mechanism

Answer 40

(cardiac) Gi so decreases cAMP and leads to increase in K+ conductance

Question 41

M3 mechanism

Answer 41

same as M1

Question 42

M4 mechanism

Answer 42

same as M2

Question 43

M5 mechanism

Answer 43

same as M1 and M3

Question 44

Activation of a nicotinic receptor causes what ionotropic effect?

Answer 44

influx in Na+

Question 45

What are the excitatory amino acid neurotransmitters?

Answer 45

Glutamate, Aspartate, possibly taurine

Question 46

what are the inhibitory amino acid neurotransmitters?

Answer 46

GABA and Glycine

Question 47

Location of GABA

Answer 47

Cerebellum, Cortex, also retina

Question 48

Enzyme for synthesis of GABA from glutamate?

Answer 48

GAD

Question 49

When GABA is reuptaked into the cell what is cotransported with it?

Answer 49

NaCl

Question 50

Which GABA receptor is ionotropic and what ion does it cause an influx in?

Answer 50

GABAa; Cl- (typical IPSP)

Question 51

Which GABA receptor is metabotropic?

Answer 51

GABAb

Question 52

What are the heterodimer effects of a GABAb receptor?

Answer 52

Gi: decrease adenylyl cyclase -> K+ influx hyperpolarization Gq: DECREASE IP3/DAG -> decrease calcium influx OVERALL ipsp but slower

Question 53

Glycine is located where?

Answer 53

Spinal Cord; does to the spinal cord what GABA does for brain

Question 54

Central locations of Ach?

Answer 54

Pons and midbrain

Question 55

How many nicotinic Ach subunits are there?

Answer 55

5; changing subunits changes how channel behaves

Question 56

What else can potentiate the GABAa receptor?

Answer 56

benzodiazepine

Question 57

What can free floating GABA bind to?

Answer 57

extra synaptic GABA receptors. mostly GABAa

Question 58

What is clinically used to mimic free floating GABA to bind to extra synaptic GABA receptors?

Answer 58

general anesthetics

Question 59

What blocks the ionotropic glycine receptor?

Answer 59

Strychnine

Question 60

Where are opioids found?

Answer 60

- Basal Ganglia - Hypothalamus - parabrachial and raphe nuclei

Question 61

What kind of receptors are opioid receptors?

Answer 61

Serpentine; Gi

Question 62

Where are endocannabinoids found?

Answer 62

Hippocampus - memory Basal Ganglia - Affect motor Spinal Cord - modulation of nociception

Question 63

Proenkephalin gives rise to which 2 opioids?

Answer 63

Met-enkephalin | Leu-enkephalin

Question 64

What opioid does the precursor POMC give rise to?

Answer 64

Beta-endorphins

Question 65

What opioid does the precursor Prodynorphin give rise to?

Answer 65

3 molecules of Leu-enkephalin and 2 different dynorphins

Question 66

Orphanin FQ is the same as what?

Answer 66

nociceptin

Question 67

What enzymes break down opioids after reuptake?

Answer 67

Enkephalinase A and B | Aminopeptidase

Question 68

What kind of receptors are All of the opioid receptors?

Answer 68

Serpentine (Gi protein linked)

Question 69

What are the effects of binding to a mu opioid receptor?

Answer 69

- analgesia - respiratory depression - EUPHORIA - sedation - constipation

Question 70

What are the effects of binding to a kappa opioid receptor?

Answer 70

- analgesia - diuresis - miosis - DYSPHORIA

Question 71

What are the effects of binding to a delta opioid receptor?

Answer 71

Only analgesia

Question 72

What is the indirect ion effect of the mu opioid receptor?

Answer 72

increase K efflux thus hyperpolarization

Question 73

What is the indirect ion effect of the kappa and delta receptors?

Answer 73

Decrease calcium in the cell

Question 74

What is the main location of opioids?

Answer 74

hypothalamus and brain

Question 75

What are the 2 endogenous endocannabinoids?

Answer 75

Anandamide and 2-Arachidonylglycerol

Question 76

What is the common molecule between Anandamide and 2-Arachidonylglycerol?

Answer 76

Arachidonic acid