Presynaptic

Question 1

how are signals transmitter between neurons

Answer 1

via synapses
synaptic transmission

Question 2

what is the reticular theory

Answer 2

the NS was made of continuous mesh of nerve cell processes (axons and dendrites)

Question 3

how neurons actually work

Answer 3

individual contiguous cells - neurons
not continuous

Question 4

2 types of synapse

Answer 4

chemical and electrical

Question 5

size of synaptic cleft

Answer 5

20nm
concentration can change rapidly

Question 6

chemical synapse

Answer 6

signals transmitter through chemical messengers . neurotransmitters

Question 7

synaptic vesicle structure

Answer 7

balls of lipid membrane
40 nm in diameter

Question 8

individual neuorn releases …

Answer 8

one type of neurotransmitter
e.g glutamatergic GABAergic dopaminergic

Question 9

what are neurotransmitters transported into vesicles via

Answer 9

proton antiporters

Question 10

what generates a proton gradient across vesicle membrane

Answer 10

ATPase

Question 11

what is the proton gradient used for

Answer 11

vesicle transporters use gradient to drive the transport of transmitters into secretory vesicles by coupling the translocation of transmitter to H+

Question 12

function of membrane protein on synaptic vesicle

Answer 12

multitude of membrane bound proteins
* docking at presynaptic membrane
* release of neurotransmitter
* filling vesicle with neurotransmitter

Question 13

transporter of GABA

Answer 13

VGAT

Question 14

transporter of glutamate

Answer 14

VGLUTs

Question 15

transporter of ACh

Answer 15

VAChT

Question 16

transporter of MA

Answer 16

VMATs

Question 17

what is crucial for neurotransmitter release

Answer 17

calcium entry
triggered by AP

Question 18

what type of calcium channels are on presynaptic vesicle

Answer 18

voltage dependent calcium channel s

Question 19

role of SNARE proteins

Answer 19

Bring synaptic vesicle close to membrane

Question 20

how are vesicle brought and fused to the membrane

Answer 20

brought by SNARE proteins
close to membrane = dock to membrane
docking and calcium sensing proteins
calcium triggered exocytosis
endocytosis vis Cathrin coated vesicles

Question 21

what is the cable transmission of neurons

Answer 21

axon

Question 22

what part of the axon does an AP initiate

Answer 22

Axon initial segment (AIS)

Question 23

structure of Axon initial segment

Answer 23

• high density of voltage gated ion channels
• membrane proteins
• unique repertoire of sub membranous cytoskeletal scaffolds
• generate and shape ap before they are propagated

Question 24

what boundary does Axon initial segment lie

Answer 24

between somatodendritic and axonal compartments

Question 25

what are axon collaterals

Answer 25

side branches of the axon that allow the neuron to send information to others

Question 26

where are synapses located

Answer 26

boutons terminaux en passant boutons

Question 27

probability of synaptic release

Answer 27

stochastic (rendom) probability 0-1 not the same at all synapses synaptic and changed by physiological factors

Question 28

what is increased by increased probability of release at synapses

Answer 28

synaptic strength goes up at Probability of release 0 = no synaptic communication

Question 29

calculate Pr (probability of release)

Answer 29

Pr = mean number of synapses releasing per trial / total number of synapses

Question 30

how to change probability of release

Answer 30

change local intracellular calcium conc

Question 31

ways to alter presynaptic calcium entry

Answer 31

* change extracellular calcium conc * apply blockers of presynaptic calcium channels * activate presynaptic receptors that alter calcium channel activity

Question 32

short term synaptic plasticity

Answer 32

short lived changes in the strength of synaptic coupling that reflect the prior experience/ activity of the synapse

Question 33

what underpins short term synaptic plasticity

Answer 33

dynamic changes in release probability

Question 34

what's the Schaffer collateral commissural pathway (SCCP)

Answer 34

connection between CA3 and CA1 pyramidal neurons

Question 35

experiment into short and long term plasticity

Answer 35

Schaffer collateral commissural pathway in hippocampus

Question 36

how to fins an excitation post synaptic potential (EPSP) recording

Answer 36

- place extracellular stimulating electrode on the axons of CA3 neurone - place an extracellular stimulating electrode in the dendritic region of CA1 - record the EPSP

Question 37

frequency =

Answer 37

1/ time period

Question 38

what do low frequency responses mean in SCCP experiment

Answer 38

stable response - little plasticity

Question 39

what do changes in paired pulse ration reflex

Answer 39

transient change in release probability

Question 40

paired pulse facilitation

Answer 40

second response (when stimulated) is bigger than the first

Question 41

paired pulse depression

Answer 41

second response lower than first

Question 42

do synapses with a low Pr tend to exhibit paired pulse facilitation or paired pulse depression

Answer 42

paired pulse facilitation

Question 43

do synapses with a high Pr tend to exhibit paired pulse facilitation or paired pulse depression

Answer 43

paired pulse depression

Question 44

Why are you more likely to get facilitation when the synapse has low Pr?

Answer 44

Readily release pool vesicle that did not release NTs the first time are ready for second AP to be release more vesicles and more NTs

Question 45

why do synapses with high Pr get depression

Answer 45

Fewer vesicles - fewer Nts left as they were release in first AP

Question 46

what determines short term plasticity

Answer 46

number of vesicles release (presynaptic)

Question 47

Low probability of release (Pr) effect on vesicle release

Answer 47

few vesicles released more vesicles released in response to second action potential = FACILITATION

Question 48

high probability of release (Pr) effect on vesicle release

Answer 48

many vesicle released fewer vesicles available for RRP = DEPRESSION

Question 49

lower calcium release and its effect on paired pulse depression

Answer 49

less calcium entry lower release probability after the first stimulation less paired pulse depression

Question 50

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