Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Y2 - CNS > Lecture 3 - Cellular Physiology Of The Brain > Flashcards

Lecture 3 - Cellular Physiology Of The Brain Flashcards

(99 cards)

Start Studying
1
Q

What are the 2 main cellular components of the nervous systems?

A

Neurones
Supporting glia

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

What are the 3 major types of glia in the CNS?

A

Astrocytes
Oligodendrocytes
Microglia

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

What is the main overall function of glial cells?

A

Nourish neurones
Insulate neurones
Remove waste

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

What is the most abundant type of glial cell?

A

Astrocyte

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

What are the roles of Astrocytes?

A

Structural support
Nutritional support
Re-uptake of neurotransmitters
Maintain ion conecentrations in Extracellular fluid
Contributes to BBB
Help repair neural damage

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

How do Astrocytes provide nutritional support to the CNS?

A

Converts glucose to lactate so that it can be transferred into the neurones

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

What is the pathway for carbohydrate uptake into neurones?

A

Glucose into Astrocyte via GLUT3
Then converted into lactate
Lactate transported into neurone via MCT1

Or

Glucose transported by GLUT1 in apical and basal surface of endothelial cell to interstitial space
Glucose then transported from interstitial space to neurone by GLUT3 in neuorlemma

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

Why is it important that Astrocytes re take up neurotransmitters?

A

Sometimes they leak out of synapses

This could lead to excessive activation of receptors

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

Which ion concentration in particular has its concentration controlled by the Astrocytes in the extracelllar fluid?

A

Potassium since it’s released in. Large quantities in highly active areas of brain

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

How do Astrocytes contribute to the blood brain barrier?

A

Induce expression of tight junctions. Between brain and endothelial cells

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

How are gap junctions between. Astrocytes important?

A

Forms a syynctium allowing calcium waves to propagate through all of the Astrocytes which may help with cognitive function

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

How many synapses do Astrocytes form?

A

3

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

What is the main function of Oligodendrocytes?

A

Myelination of neurones in the Central Nervous System

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

What cells myelinate neurones of the PNS?

A

Schwann cells

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

What cell is damaged in multiple sclerosis?

A

Oligodendrocytes

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

What is an example of a neurodegernative disorder that affects schwann cells? (PNS)

A

Guillain-Barre Syndrome

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

What is the main function of microglia?

A

Major immune cell in the CNS

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

What type of immune cell do Microglial resemble the most to protect the brain?

A

Macrophages

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

How does a Microglial cell appear when inactivated?

How do they appear when activated?

A

Branched appearance with their process scanning for antigens

When activated (inflammation) they become phagocytose like a macrophage

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

What positive and negative affects do Microglia have?

A

Remove debris and clean up site of damage

Negative is that they may cause collateral damage injuring cells that were not involved int he initial. Pathology

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

What is the function of the blood brain barrier?

A

To limit diffusion of substances from the blood to the brains extracellular fluid
Maintains the correct environment for neurones

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

What makes up the blood brain barrier at the brain capilarries?

A

Tight junctions between endothelial cells
Basement membrane surround capilary
End feet of Astrocyte processes

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

What are some substances that can cross the blood brain barrier?

A

Glucose
Amino acids
K+

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

What is meant by CNS Immune privileged/immune specialised?

A

The specialised immune repsonse that occurs in the brain where the CNS inhibits the initiation of the pro-inflammorty T cell response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Why does the CNS have a specialised immune response?
Since a rapid inflammatory response would lead to the brain swelling leading to rapid increase in intracranial pressure leading to ischameic hypoxia and rapid death
26
What immune cells can enter the brain?
T cells
27
What are the 4 main sections to a typical neurone?
Cell soma (body) Dendrites (projections) Axon Terminals
28
What happens at a synapse once the presynaptic terminal depolarises?
Ca2+ voltage gated ion channels open Ca2+ influx Ca2+ binds to vesicles containing neurotransmitter stimulating them to fuse with the presynaptic membrane and release the transmitter into the cleft Neurotransmitter diffuses across cleft and binds to receptors on the postsynaptic membrane
29
What is the post synaptic response once an action potential reaches the presynaptic terminal?
Once the neurotransmitter binds to the postsynaptic receptor the response depends on the nature of the neurotransmitter and the nature of the receptor
30
What are the 2 types of receptor that can. Be on the postsynaptic membrane?
Ion channel (ligand gated ion channel) G-protein coupled receptor
31
What are the 2 types of neurotransmitter?
Excitatory Inhibitory
32
What is an example of an excitatory neurotransmitter?
Glutamate
33
What is an example of an inhibitory neurotransmiter?
GABA
34
What are the 3 chemical classes of neurotransmitters?
Amino acids Bio genic amines Peptides
35
What is the main excitatory amino acid neurotransmitter found all over the CNS?
Glutamate
36
What are the 2 main inhibitory amino acid neurotransmitters?
GABA Glycine
37
What are the 2 main types of glutamate receptors?
Inotropic receptors (ion channel) Metabotropic (G protein coupled receptor)
38
What is an inotropic glutamte receptor?
Ion channel where activation causes depolarisation if its a glutamate receptor causing cation influx
39
What is a metabotropic glutamte receptor?
G protein coupled receptor that’s linked to either changes in IP3 and Ca2+ Or ihbitrion of adenylate cyclase and decreased cAMP levels
40
Where is GABA a very prevalent neurotransmitter in the brain?
Cerbral cortex and basal ganglia
41
What type of neurotransmitter is GABA?
Inhibotry amino acid neurotransmitter
42
What are the 2 types of receptors that use the inhibotry amino acid neurotransmitter GABA?
Ionotropic Metabotropic
43
What ligand gated ion channels are important at synapses that uses glutamate (excitatory synapse)?
AMPA NDMA
44
What is the role of AMPA receptors at glutamatergic synapses?
Mediate fast initial depolarisation
45
What ion are NMDA receptors at glutamateric synapses permeable to?
Ca2+ (Glutamte needs to bind to NMDA and cell needs to be depolarised for Ca2+ to flow)
46
What is the co-agonist for NMDA except for glutamte?
Glycine
47
What brain function does glutamte receptors. Have?
Learning and memory
48
How are glutamate receptors improtant in learning and memory?
Activation of NMDA receptors can up regulate AMPA receptors Strong high frequency stimulation causes long term potentiation Ca2+ entry through NMDA receptors important for induction of Long Term potentiation
49
What causes excitotoxicity?
Too much Ca2+ entry through NMDA receptors Too much glutamate
50
What is the main inhibitory amino acid in the brain ?
GABA
51
Where does glycine act mostly as an inhbitory neurotransmitter?
Brainstem and spinal cord
52
What is the method that GABA and Glycine acts as an inhibitory neurotransmitter?
GABAa and glycine receptors have integral Cl- channels Opening Cl- channels leads to Cl- influx into neurone leading to hyperpolarisation causing an inhbitory post-synaptic potential which decreases the firing of action potentials
53
What 2 drug types increase the activity of GABA receptors in the brain?
Barbiturates Benzodiazepines
54
What effects do barbiturates and benzodiazepines have by enhancing the response of GABA receptors to the inhbitory neurotransmitter GABA?
Anxiolytic and sedative But barbiturates not used for this anymore
55
Why are barbiturates not used for anxiolytics and sedatives anymore? What is it sometimes used for?
Risk of fatal OD, dependance and tolerance Antiepileptic
56
What is benzodiazepines used to treat?
Anxiety Insomnia Epilepsy
57
What type of neurones use glycine as an inhibitor neurotransmitter?
Inhbitory interneuroens (neurones between neurones)
58
What is the function of glycine released in the spinal cord during REM sleep?
Inhibits lower motor neurones (LMN) causing paralysis
59
What are biogenic amine neurotransmitters typically used for?
Modulators role in specific brain pathways
60
What are the main biogenic amine neurotransmitters?
ACh Noradrenaline Dopamine 5-HT (serotonin) Histamine
61
Where is ACh used as a neurotransmitter?
Neuromuscular junctions Ganglion synapse in autonomic nervous system Postganglionic parasympathetic Sympathetic cholinergic fibres like to sweat glands Nicotine and Muscarinic receptors in the brain (Mainly excitatory) They are often on presynaptic terminals to enhance the release of other transmitters
62
What neurotransmitter does Ach aid in the release of in the brain?
Dopamine
63
What causes addiction with smoking?
Activation of nicotinic receptors leads to release of dopamine (a reward substance)
64
Where do cholinergic neurones originate from in the CNS?
Basal forebrain and brainstem
65
Where do cholinergic neurones give projections to?
Parts of cortex and hippocampus
66
What is an example of an area of the brain containing local cholinergic interneurones?
Corpus striatum
67
What are the key pathways produced by the basal forebrain nuclei projecting to cortical areas?
Arousal Learning and memory Motor control
68
How may anticholinergic drugs affect the brain and why?
Drowsiness Pathway for arousal is ACh mediated
69
What causes Alzheimer’s disease?
The degeneration of cholinergic neurones in the nucelus basalis
70
What type of drugs are given to alleviate symptoms of Alzheimer’s disease?
Cholinesterase inhbitors
71
What 2 main pathways in the brain are involved in mood, arousal and reward?
Mesocortical pathway Mesolimbic pathway
72
What is the pathway involved in motor control?
Nigrostriatal pathway
73
What is the nigrostriatal pathway?
Pathway from substantia nigra to the striatum involved in motor control
74
What causes Parkinson’s disease?
Degeneration of the nigrostriatal pathway Or Associated with loss of dopaminergic neurones
75
How is Parkinson’s treated? How does this work?
Levodopa Converted to dopamine by DOPA decarboxylase
76
What causes schizophrenia?
To much dopamine being released E.g amphetamine releases dopamine and noradrenaline this produces schizophrenic like behaviour
77
How do antipsychotic drugs normally work? How is schizophrenia treated?
Antagonists to dopamine receptors D2 receptor antagonist
78
What is the mesolimbic pathway? What neurotransmitter does it use?
From midbrain to limbic system (hippocampus, amygdala) Important in mood arousal and reward Dopamine
79
What disease does over activity of the mesolimbic system contribute to?
Schizophrenia
80
What is the neocortical pathway?
Dopamine pathway from midbrain to cerebral cortex
81
What drug is given for Parkinson’s disease?
L-DOPA with Carbidopa
82
How does L-DOPA and Carbidopa help treat Parkinson’s?
L-DOPA converted to dopamine in brain by enzyme aromatic amino acid decarboxylase L_DOPA readily crosses BBB L-DOPA can problematically be converted to dopamine in the periphery’s Carbidopa stops this (inhibits AADC in the periphery) Carbidopa cant cross the blood brain barrier
83
What are the negative side effects oof high dopamine in the periphery?
Heart GI and urinary side effects
84
What type of receptors does noradrenaline work on/
GPCRs
85
Where are the cell bodies for noradrenaline found ?
Brainstem like in the locus coeruleus
86
What role does noradrenaline serve in the brain?
Behavioural arousal
87
How do locus coeruleus neurones act during sleep then waking?
These noradrenaline mediated neurones are inactive in sleep and activity increase when waking
88
What affect do amphetamines have on the brain?
Increase levels of noradrenaline and wakefulness (locus. Coeruleus)
89
What condition is associated with a deficieny of noradrenaline?
Depression
90
How is depression treated?
Drugs that increase noradrenaline in the brain
91
How are serotonergic pathways distributed through the CNS?
Similar distribution to noradrenergic neurones
92
What is the function of serotonin (sertonergic) pathways in the CNS?
Sleep and wakefulness Mood
93
Where do 5-HT/serotonin neurones originate from?
Raphe nuclei of brainstem
94
What can low levels of serotonin cause?
Depression
95
What drugs can be used to help treat depression and anxiety when serotonin is deficient?
Selective serotonin re uptake inhibitors
96
What is an example of an SSRI?
Fluoxetine (also called Prozac)
97
What are some peptide neurotransmitters involved in pain transmission?
Dynorphin Encephalitis
98
What is an excitroary post synaptic potential?
The depolarisation in the post synaptic membrane following a ligand binding to an ioniotropic receptor leading to an influx of cations causing depolarisation
99
How does more neurotransmitter in synapse affect the excitatory post. Synaptic potential?
Inc magnitude of excitiory post synaptic potential Increased frequcney of action potentials

Y2 - CNS (21 decks)

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