Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuroscience > Neurotransmission > Flashcards

Neurotransmission Flashcards

(63 cards)

Start Studying
1
Q

List the types of neurotransmitters in the CNS

A

Amino acids (glutamate, GABA, glycine)

Gaseous molecules (NO, CO)

Miscellaneous (purines, endocannabinoids)

Monoamines: Catecholamines (noradrenaline, dopamine), Indoleamines (5-hydroxtryptamine/ 5-HT), Others (melatonin, histamine)

Acetylcholine

Peptides:
Hypothalamic releasing factors (eg. somatostatin), Tachykinins (eg. Substance P), Opioids (eg. enkephalins), Others (eg. CCK, NPY, orexin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the types of monoamines?

A

Catecholamines (noradrenaline, dopamine), Indoleamines (5-hydroxtryptamine/ 5-HT), Others (melatonin, histamine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What signalling predominates in the cortex?

A

Interlaminar glutamate or GABA neurons, Local circuit GABA, gaseous or peptide

Cortico-cortical glutamate neurons

Cortico-subcortical glutamate neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What signalling predominates in the brain stem?

A

Monoamine/ACh projecting to higher centers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What signalling predominates in the subcortical regions (cerebellum, striatum, thalamus and spinal cord)?

A

Local circuit neurons GABA and peptides

Projecting GABA and peptide neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the criteria to localize a neurotransmitter to a neuron?

A

Neuronal localization: the neurotransmitter must be localized in the neuron including; the transmitter candidate itself, biosynthetic/metabolic enzymes, reuptake mechanisms and appropriate receptors

Synaptic mimicry: must be proven to occur by a different exogenous transmitter or receptor agonist, compare responses.

Neurotransmitter versus neuromodulator: must be understood if it transmits or just modulates

Neuronal release: must be evidence of release from neuron (sample supernatant produced)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an EPSP and an IPSP?

A

Excitatory post synaptic potential (depolarization) and inhibitory post synaptic potential (hyperpolerization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is pre-synaptic inhibition?

A

Presynaptic inhibition is an inhibitory input to a neuron to make it less likely to fire an action potential

GABA receptors are activated, it causes a chloride influx, which hyperpolarizes the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are excitatory amino acids?

A

Glutamate

aspartate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where are glutamate neurotransmitters located?

A

Cortico-cortical and cortico-subcortical neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is glutamate synthesised?

A

De novo synthesis from glucose and from glutamine supplied by glial cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What packages glutamate into vesicles?

A

Vesicular glutamate transporters (vGluTs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What receptors does glutamate bind to?

A

Ionotropic (ligand-gated ion channels) AMPA, NMDA, Kainate
(evoke fast EPSPs)

Metabotropic (G-protein coupled receptors) (mGlu1-8)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the NMDA receptor allow through?

A

Na+, Ca2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the action of ketamine?

A

NMDA blocking drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is glutamate cleared from the synapse?

A

Excitatory amino acid transporters (EAATs) on neighbouring glial cells (EAAT1 and EAAT2).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to glutamate within the glial cell?

A

Glutamate is converted to glutamine by glutamine synthetase

Glutamine is subsequently released by System N transporters and taken up by neurons through System A sodium-coupled amino acid transporters to complete the glutamate–glutamine cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the functions of glutamate?

A

Memory: long term potentiation (LTP) is mediated by glutamate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe excitotoxicity

A

Ischemia (hypoxia/hypoglycemia) leads to excess release of glutamate overstimulation of NMDA receptors - excessive Ca2+ entry into neurons - cell death.

NMDA receptor antagonists reduce cell death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the inhibitory amino acids?

A

GABA and glycine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What neurons release GABA/glycine?

A

Cortical interneurons, sub-cortical neurons (eg. basal ganglia).

Glycine in spinal cord interneurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is GABA synthesised?

A

From glutamate (Glu) by glutamate decarboxylase (GAD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the GABA receptors?

A

GABAa receptor (Cl- channel) (Ionotropic GABAA receptors evoke fast inhibitory postsynaptic potentials (IPSPs))

GABAb (Gi-protein coupled)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe the GABAa channel

A

Ligand-gated ion channel (Cl-)

Pentameric structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What role do GABAa blocking drugs have?
Channel blocking agents are convulsant agents.
26
How is GABA neurotransmission terminated?
Uptake of GABA by GABA transporter 2/3 (GAT 2/3) into astrocytes
27
What happens to GABA in astrocytes?
GABA transaminase (GABAT) converts it into succinic semialdehyde (SSA). SSA is then oxidized by SSADH to succinate and serves as a substrate within the tricarboxylic acid (TCA) cycle.
28
What is the role of GABA?
Movement control: GABA is a major transmitter in the basal ganglia.
29
What disease affecting movement is due to loss of GABAergic neurons?
Huntington’s disease due to loss of GABA-containing long projection neurones (striatopallidal) leads to uncontrolled movement.
30
What do many anti-epileptic drugs target?
Anticonvulsants increase GABA transmission by facilitating GABAA receptor function (eg. benzodiazepines, barbiturates) Inhibiting GABA metabolism (valproate) or uptake (tiagabine).
31
Where are CNS ACh receptors located?
ACh neurons located in basal forebrain, septum and striatum.
32
What are the ACh receptor subtypes?
Muscarinic (metabotropic) | Nicotinic (ionotropic)
33
What are the CNS functions of acetylcholine?
Movement control: muscarinic antagonists (benzatropine) helpful in relief of tremor in Parkinson’s disease. Reward and motivation: addiction to nicotine related to ACh interaction with midbrain dopamine (mesolimbic) pathways. Memory: lesion of cholinergic pathways and muscarinic antagonists induce amnesia.
34
What are peptide neurotransmitters stored in?
Dense cored vesicle, released by exocytosis
35
What are tachykinins?
Substance P and the Neurokinins
36
What are tachykinin receptors?
Slow excitatory responses via G-protein coupled receptors (NK1-3).
37
Where is substance P localised to?
Primary sensory afferents (pain pathways), medulla (vomiting centre) and limbic system (anxiety pathways).
38
What is the role of substance P?
Emesis, pain processes, and behavioural response to anxiety & stress.
39
What are the opioid receptors?
µ, d, k: inhibitory, G-protein coupled. CNS effects mainly mediated by inhibitory µ receptors.
40
Role of opioid receptors
Pain transmission: opiate analgesics (eg. morphine) act on µ receptors in the spinal cord to relieve pain (also limbic system & brainstem). Reward and motivation: morphine euphoria & addiction linked to opioid interaction with midbrain dopamine (mesolimbic) pathways.
41
Chemistry of monoamine transmitters?
Contain one amino group connected to an aromatic ring by a two-carbon chain.
42
Where do dopamine neurons innervate mainly?
Basal ganglia (striatum)
43
Where is there a large amount of dopaminergic neurons?
Substantia nigra compacta Locus coeruleus (NA) Reticular formation Nucleus raphe (5HT)
44
Describe the firing of monoamine neurons, what does this mean?
Fire spontaneously and rhythmically, this provides a constant level of tone at the neuronal target - making modulation especially important.
45
Function of monoamine neurons
Global arousal pathways (5HT) Reward and behaviour (dopamine)
46
How is noradrenalin transported from cytosol to vesicle?
Vesicular monoamine transporter (VMAT)
47
How is noradrenaline removed from the synapse?
UT1 mechanism via NET transporter into cytosol, broken down by MAO or repackaged. UT2 into postsynapse, digested by COMT
48
Therapeutic uses of drugs targeting noradrenaline synapses
Anxiety: b-adrenoceptor antagonists (propranolol) are anxiolytic Attention hyperactivity deficit disorder: Noradrenaline-releasing agents (ritalin and amphetamine) are therapeutically useful in ADHD Depression: Noradrenaline reuptake inhibitors (reboxetine) and MAO inhibitors (phenelzine) are antidepressant.
49
How is dopamine transported from the cytosol into synaptic vesicles?
Vesicular monoamine transporter, VMAT2
50
What are the dopamine receptors?
Postsynaptic dopamine receptors, located on dendrites (the postsynaptic neuron), or presynaptic autoreceptors ( D2 and presynaptic D3 receptors),
51
Therapeutic uses of drugs targeting dopamine synapses
Parkinsons disease: L-DOPA, dopamine agonists (ropinerole), COMT inhibitors (tolcapone) are used in the treatment of Parkinson’s disease. Schizophrenia: Dopamine receptor antagonists (haloperidol) are antipsychotic. Addiction: Partial dopamine receptor agonists (buproprion) help manage relapse to tobacco smoking. Bipolar depression: Dopamine receptor antagonists (haloperidol) are anti-manic agent
52
Describe the serotonin receptors
Except for the 5-HT3 receptor, a ligand-gated ion channel, all other 5-HT receptors are G-protein-coupled receptors
53
Therapeutic uses of drugs targeting 5-HT synapses
Depression: Selective 5-HT (serotonin) reuptake inhibitors (fluoxetine) are antidepressant Schizophrenia: Non-selective 5-HT2 receptor antagonists (risperidone) are antipsychotic. Migraine: 5-HT1B/D agonists (sumatriptan) Nausea and vomiting: 5-HT3 receptor antagonists (ondansetron) are antiemetic
54
What is the underlying cause of epilepsy?
Excessive and abnormal neuronal activity in the cortex of the brain.
55
What can a hyperexcitable state arise from (epilepsy)?
Increased excitatory synaptic neurotransmission, Decreased inhibitory neurotransmission, An alteration in voltage-gated ion channels, An alteration of intra- or extra-cellular ion concentrations in favour of membrane depolarization.
56
How can epilepsy be treated by antagonising excitable neurotransmission?
NMDA, AMPA, Kainate antagonists
57
How can epilepsy be treated with agonising inhibitory neurotransmission?
GABAa agonists, Barbiturates and benzodiazepines act by positive modulation Vigabatrin acts by inhibiting GABA metabolism Tiagabine, an inhibitor of the high-affinity GABA transporter GAT1.
58
How can epilepsy be treated through modulation of voltage gated sodium and calcium channels?
Sodium channel-blocking AEDs, phenytoin, carbamazepine and lamotrigine. Inhibit high-frequency repetitive spike firing during seizure spread Gabapentin binds to calcium channel subunits Might inhibit calcium currents, resulting in reduced excitatory neurotransmission. Ethosuximide inhibits T-type calcium channels
59
The receptor involved in hippocampal long term potentiation
NMDA
60
Which neurotransmitter is released from retinal photoreceptors?
Glutamate
61
A neuropeptide involved in suppressing nociceptive transmission
Neuropeptide Y
62
NMDA receptors
Excitatory/ionotropic/Bind glutamate/require depolarisation to remove Mg2+ before channel can open/important in LTP
63
Neurotransmitter released from granule cells in the cerebellum is
Glutamate

Neuroscience (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions