Excitatory NTs

Question 1

What type of synapses are excitatory in their actions?

Answer 1

Type I

Question 2

What do excitatory NTs do?

Answer 2

Stimulate the brain by firing action potentials. This is due to the opening of channels allow positive ions in.

Question 3

List some examples of excitatory NTs.

Answer 3

• Glutamate - most common NT of CNS
• Acetylcholine
• Catecholamines (dopamine, adrenaline, noradrenaline)
• Serotonin

Question 4

How does glutamate work?

Answer 4

Interacts with glutamate receptors, allows sodium in, depolarisation.

Question 5

What is the function of glutamate?

Answer 5

• Important in learning and memory

- Important in potentiation (strengthening of signal transmission between specific neurons and how NS adapts over time)

Question 6

What is the consequence of excessive glutamate in synapses?

Answer 6

Excitotoxicity which can damage or kill neurons - linked with Parkinson’s, Alzheimer’s, MS, epilepsy.

Question 7

How do catecholamines work?

Answer 7

Bind GPCRs in brain.

Question 8

What is the function of catecholamines?

Answer 8

Increase heart rate and blood pressure, bring NS to high alert.

Question 9

How does serotonin work?

Answer 9

Found in raphe region of pons and upper brain stem extending to forebrain. Binds ligand-gated ion channels.

Question 10

What is the function of serotonin?

Answer 10

Regulates sleep and wakefulness.