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Flashcards in Synaptic transmission Deck (21)
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1
Q

What causes the release of neurotransmitter?

A

Presynaptic action potential

2
Q

Can neurotransmitters be released even without Nav and Kv channels?

A

Yes, if membrane can be artificially depolarized

3
Q

What causes neurotransmitter release during an action potential?

A

Presynaptic Ca2+ influx via voltage-gated Ca2+ channels

4
Q

Calmodulin dependent kinase can mobilize neurotansmitters how?

A

Initiate exocytosis

Replenish releasable pool

5
Q

What is docking?

A

Trafficking of transmitters to docking protein, Rab3 (GTP-binding), for release

6
Q

What is the release mechanism for the storage pool of neurotransmitters

A

Synapsins link vesicles to cytoskeleton

Calmodulin kinase modulates these links

During Ca2+ influx, Rab3A binds to rabphillin on vesicles and directs them to targetin vsciles & docking site

7
Q

What proteins are required for transfer of neurotransmitters to releasable pool?

A

Mammalian uncoordinated-13 (18)

8
Q

What is the mechanism for release of the slowly releasable/readily releasable pool?

A

Vesicles dock via v-SNAREs and target t-SNAREs

9
Q

Name common v-SNARES

A

synaptobrevin

VAMP

10
Q

Name common t-SNAREs

A

syntaxin, neurexin, SNAP-25

11
Q

What SNARE is targeted by the tetanus toxin?

A

Synaptobrevin

12
Q

What SNARE is targeted by the botulinum A toxin?

A

SNAP-25

13
Q

What is the function of synaptoagmin?

A

Modulates Ca2+ dependent exocytosis

14
Q

Synaptic release of how many vesicles within 1-2ms will depolarize the neuromuscular postsynaptic membrane to 0mV?

A

100-300

15
Q

What may account for 90% of neurotransmitter release?

A

Quantal (spontaneous) release

16
Q

How far does the quantal release of neurotransmitter diffuse? How long does this take?

A

20-50 nm in 2ms

17
Q

Are diffusion rates fast or slow?

A

Fast

18
Q

Are dissociation rates fast or slow?

A

fast

19
Q

Are opening & closing rates fast or slow?

A

Fast

20
Q

Are desensitization rates and internalization rates fast or slow?

A

slow

21
Q

What is the rate limiting step of synaptic transmission?

A

Recovery rate