Glia and Neurotransmitters Flashcards Preview

Phase 1 - S4 Nervous System > Glia and Neurotransmitters > Flashcards

Flashcards in Glia and Neurotransmitters Deck (36)
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1

what are the types of glial cells

astrocytes, oligodendrites and microglia

2

what do astrocytes do (5)

structurally support the neurones
provide nutrition to neurones
removes excess neurotransmitters
buffer K levels
help form the BBB

3

how do astrocytes provide nutrition for neurones

as neurones cant store glycogen, astrocytes take in glucose and store it as lactate. this can then be converted to pyruvate to be transported to the neurones when glucose is low

4

what neurotransmitter is particularly toxic to neurones

glutamate

5

how do astrocytes help form the blood brain barrier

they help form the tight junctions between endothelial cells

6

what do oligodendrites do

myelinate the axons in the CNS to give insulation

7

what cells myelinate the neurones in the PNS

Schwann cells

8

true or false: each oligodendrite can only myelinate one axon at a time

false- they can myelinate may at one time

9

what do microglia do

they recognise foreign bodies and become activated into phagocytes

10

describe the release of neurotransmitters at synapses

depolarisation in the pre-synpatic bulb causes the influx of calcium ions.
Ca ions causes the vesicles containing the neurotransmitter to fuse with the pre-synpatic membrane to be released into the synaptic cleft.
the neurotransmitter then binds to receptors on the post-synaptic membrane to cause either activation/inhibition.

11

true or false; glutamate is excitatory

true

12

what receptors does glutamate bind to

GPCRs, AMPA and NMDA

13

describe what happens when glutamate binds to AMPA receptors

causes fast depolarisation as the receptors are linked to Na/K channels so sodium moves into the cell.
the depolarisation also allows activation of the NMDA receptors

14

when do NMDA receptors become activated

when glutamate binds and when the neurone is depolarised due to AMPA receptors

15

what does activation of NMDA receptors lead to

opening of calcium channels leads to calcium influx

16

what is the calcium influx through NMDA important for

learning and memory

17

why is too much glutamate toxic to cells

lots of AMPA are activated so the neurones depolarise more - therefore, more NMDA are activated so lots of calcium is taken into the cell which is excitotoxicity

18

name 3 types of amino acid neurotransmitters

glutamate, GABA and glycine

19

what is excitatory postsynaptic potential

where depolarisation occur in the post-synpatiic bulb following neurotransmitter release

20

what is inhibitory postsynaptic potential

where hyper polarisation occurs in the post synaptic bulb following neurotransmitter release

21

how do GABA and glycine cause hyper polarisation in the post-synaptic bulb

they are linked with chloride channels so the influx of chloride ions causes hyperpolarisation

22

what drug types enhance GABA receptors

barbiturates and benzodiazepines

23

what are drugs which enhance GABA receptors used to treat

epilepsy, anxiety and insomnia

24

where is acetyl choline released from in the CNS

Nucleus basalis

25

where does acetyl choline travel to in the CNS

hippocampus and cortex

26

which neurones are the first to die in Alzheimer's

nucleus basalis

27

what drugs are given to help the symptoms of Alzheimers

cholinesterase inhibitors

28

where is dopamine released from in the CNS

mesocortical pathway, mesolimbic pathway and nigrostriatal pathway

29

what is the nigrostriatal pathway involved in

motor control

30

what neurones are the first to die in Parkinson's

nigrostriatal pathway