Neurotransmitters and Receptors

Question 1

What are the major neurotransmitters found in the reward circuit?

Answer 1

Dopamine
Glutamate
GABA

Question 2

What is a catecholamine?

Answer 2

Monoamine neurotransmitters made by the adrenal gland

Question 3

What is dopamine the primary driver of?

Answer 3

The reward circuit

Question 4

Where is dopamine particularly important?

Answer 4

The second phase of the reward circuit, VTA -> NAc

Question 5

What neurotransmitters are catecholamines?

Answer 5

Dopamine
Norepinephrine

Question 6

Where is a major source of NE projections in the brain?

Answer 6

From the locus coeruleus

Question 7

What neurotransmitter plays a big role in stress-induced relapse?

Answer 7

Norepinephrine

Question 8

What is GABA?

Answer 8

A major inhibitory neurotransmitter

Question 9

What is GABA central to?

Answer 9

To disinhibitory mechanisms of reward

Question 10

What is glutamate?

Answer 10

An amino acid

Question 11

What does glutamate play a major role in?

Answer 11

Cue-triggered relapse
LTP/LTD plasticity

Question 12

What is serotonin?

Answer 12

Monoamine indole

Question 13

Where is a major source of serotonin found?

Answer 13

In the raphe nuclei

Question 14

There is a link between low serotonin and what?

Answer 14

Impulsivity and violence in addicts

Question 15

How many genes are there in dopamine receptors?

Answer 15

5

Question 16

What do D1-like type DA receptors do?

Answer 16

Increases cytoplasmic [cAMP] via adenylyl cyclase
Stimulatory

Question 17

What do D2-like type DA receptors do?

Answer 17

Decreases cytoplasmic [cAMP] via adenylyl cyclase
Inhibitory

Question 18

What are D1-like type DA receptors responsible for?

Answer 18

Cognition

Question 19

What are D2-like type DA receptors responsible for?

Answer 19

Locomotion

Question 20

What is translational research?

Answer 20

Conducting research that translates into benefiting people
e.g. animal testing

Question 21

What does the effort exerted to self-administer drugs in animals relate to?

Answer 21

The degree of reward experienced

Question 22

What does pairing of an environment with stimulation of VTA DA-ergic projections cause?

Answer 22

Immediate place preference that will last for several days

Question 23

What does it mean if the animal spends time in the drug-paired chamber?

Answer 23

They are exhibiting drug-seeking behaviour

Question 24

What is microdialysis used for?

Answer 24

To measure neurotransmitter levels in specific nuclei directly

Question 25

What does control hedonic tone look like?

Answer 25

Tonic DA release There is a consistent baseline level of dopamine release

Question 26

How do addictive drugs affect hedonic tone?

Answer 26

Induce phasic (bursts) of dopamine firing (release) in the NAc

Question 27

Why can dopamine antagonists be used in therapy?

Answer 27

They are negative reinforcers that enhance behaviours to reduce administration

Question 28

What does a low point in fluctuating dopamine levels predict?

Answer 28

The next self-administered dose

Question 29

What happens when you develop tolerance against a drug?

Answer 29

Lowered elevation of hedonic tone during chronic use Need higher and higher doses just to feel normal

Question 30

What are AMPARs?

Answer 30

AMPA receptors for fast, excitatory transmission

Question 31

What are the characteristics of AMPARs?

Answer 31

Ionotropic Form tetramers C-terminus forms intracellular scaffolds 4 genes

Question 32

What do AMPARs play a major role in?

Answer 32

Long-term depression

Question 33

How many genes and protein units are in NMDARs?

Answer 33

7 genes (1 GluN1, 4 GluN2, 2 GluN3) 7 protein subunits

Question 34

What are NMDARs activated by?

Answer 34

Co-activated by Glu and Ser/Gly

Question 35

What type of receptors are NMDARs?

Answer 35

Ionotropic

Question 36

What are NMDARs critical for?

Answer 36

For synaptic plasticity (LTP/LTD)

Question 37

What is NMDAR signalling dependent on?

Answer 37

Ca2+

Question 38

What is excitotoxicity?

Answer 38

Cooking neurons

Question 39

What type of receptors are glutamate receptors?

Answer 39

Metabotropic

Question 40

How many genes are in glutamate receptors?

Answer 40

8 genes

Question 41

What are glutamate receptors involved in?

Answer 41

Synaptic plasticity

Question 42

What do group I Gq-linked receptors do?

Answer 42

Increase excitotoxicity risk

Question 43

What do group II/III Gi/o-linked receptors do?

Answer 43

Decrease excitotoxicity risk

Question 44

What can increased calcium lead to?

Answer 44

Increased risk of excitotoxicity

Question 45

What is LTP?

Answer 45

Strengthening of synaptic transmission between two neurons downstream of glutamate receptors

Question 46

What are the 4 things associated with LTP?

Answer 46

Specificity Associativity Cooperativity Persistence

Question 47

What is specificity?

Answer 47

Sites of LTP are confined to specific contact sites

Question 48

What is associativity?

Answer 48

Strong stimulation through one pathway will induce LTP for weak pathways at the same site

Question 49

What is cooperativity?

Answer 49

Many weak stimuli can induce LTP; constructive interference

Question 50

What is persistence?

Answer 50

Potentiation lasts minutes, weeks, and months; unique to LTP

Question 51

What is LTD?

Answer 51

Weakening of synaptic transmission between two neurons

Question 52

What does the phasic firing of VTA DA-ergic neurons generate?

Answer 52

A learning signal when an unexpected reward occurs

Question 53

What happens when a reward becomes fully predictable?

Answer 53

DA-ergic neurons are no longer triggered and learning ceases

Question 54

What does the learning signal lead to in the context of addictive drugs?

Answer 54

Drug adaptive behaviours leading to compulsive drug intake at the expense of all other behaviours

Question 55

What does NE innervation activate?

Answer 55

Sympathetic responses which plays a major role in stress-induced drug relapse

Question 56

Are drugs that target serotonin receptors more or less addictive?

Answer 56

Less

Question 57

What does ACh activate?

Answer 57

Parasympathetic responses which plays a major role in learning and memory circuits

Question 58

What is acute use?

Answer 58

One use/month, no lingering effects of use

Question 59

What is chronic use?

Answer 59

More than a month of use

Question 60

What happens to tissue over long-term periods of addiction?

Answer 60

Can become dysfunctional