C1. Brain Function and structure Part IV

Question 1

What are the two types of synapses ?

Answer 1

A. Chemical

B. Electrical

Question 2

How does chemical synapse work ?

Answer 2

Presynaptic neurones

• Synthesis of neurotransmitter (e.g. adrenaline)
• packed into vesicles for storage
• Synaptic vesicles will make their way to presynaptic terminals
• Exocytosis of the neurones into the synaptic cleft
• Bind to receptor on Prost synaptic neurone
• This causes a change in the membrane potential, change in gene expression or biological cascade
• Or other forms of termination of the neurotransmitters

Question 3

Explain how excitatory processing of information occurs and what neurotransmitters and ions are involved in this ?

Answer 3

The activation of Excitatory neurotransmitter such as glutamate diffuses out of the presynaptic neurone

This then leads to an increase in sodium ions In the pits synaptic neurone

Question 4

Explain how inhibitory processing of information occurs and what neurotransmitters as well as ions are involved ?

Answer 4

The activation of inhibitory neurotransmitters such as GABA diffuses out of the presynaptic neurone

This leads to the increase in calcium ions in the post synaptic neurone

Question 5

What is the classic neurotransmitter ?

Answer 5

Acetylcholine

Question 6

How is acetylcholine synthesise and what enzyme is involved ?

Answer 6

Acetylcholine coA + choline

Via choline-acetyltransferase

Question 7

Where is acetylcholine stored ?

Answer 7

Vesicles within the presynaptic membrane

Question 8

How is acetyl choline released ?

Answer 8

Via exocytosis

Question 9

How is acetylcholine terminated ?

Answer 9

Via enzyme acetylcholinesterase

Question 10

What is acetylcholine broken down into when it is terminated by the enzyme acetylcholinesterase ? What molecule is recycled ?

Answer 10

Acetate + Choline

Chlorine is recycled back and acetate is removed by another mechanism

Question 11

What are the bilge if amines and give and example for each one

Answer 11

Catecholamines

• Dopamine
• Noradrenaline
• Adrenaline

Indolamines
- 5-HT

Question 12

How are they synthesised ?

Answer 12

Look back at the lecture notes

Question 13

How is 5-HT synthesised ?

Answer 13

Look back at lecture notes

Question 14

What enzymes are biogenic amines terminated by ?

Answer 14

MAO

COMT

Question 15

How do amphetamines work ?

Answer 15

Cause excocytotic release of NA and DA

Question 16

How does MDMA work ?

Answer 16

Increase release if 5-HT, DA and NA