Neurotransmitter, neurotrasnmitter receptors LO4, LO5

Question 1

cholinergic receptors

Answer 1

are receptors that bind acetylcholine
- 2 types - nicotinic, muscarinic

Question 2

adrenergic receptors

Answer 2

are receptors that bind noradrenalin (and adrenalin)
- Excitatory
- subtype A and B

Question 3

Nicotinic

Answer 3

always excitatory

Question 4

Muscarinic

Answer 4

excitatory or inhibitor

Question 5

Excitatory postsynaptic
potential (EPSP)

Answer 5

1. NT binds receptors on postsynaptic membrane
2. Opens gated ion channels
3. Graded depolarization (i.e. Na+ ions enter the cell)
4. Postsynaptic cell EXCITED - membrane potential closer to threshold, therefore
5. Action potential more likely to occur
6. Overall effect ► increased
   target activity

Question 6

Inhibitory postsynaptic
potential (IPSP)

Answer 6

1. NT binds receptors on
   postsynaptic membrane
2. Opens gated ion channels
3. Graded hyperpolarization
   (i.e. K+ ions exit the cell)
4. Postsynaptic cell INHIBITED - membrane potential further from threshold, therefore …
5. Action potential less likely to occur
6. Overall effect ► decreased target activity

Question 7

Agonists

Answer 7

drugs that mimic the action of the NT –> promote
normal response

Question 8

Antagonist

Answer 8

drugs that bind the receptor and block the action of the NT –> prevent normal response

Question 9

Acetylcholine ACh

Answer 9

Motor control outside the CNS
- within CNS - cognition, memory, consciousness

Question 10

Noradrenaline

Answer 10

stimulates brain reward and
pleasure centres (“feel good” NT)
* involved in reducing stress and enhancing attention

Question 11

Dopamine

Answer 11

• stimulates brain reward and pleasure centres (“feel good” NT)
• high levels noted with schizophrenia
• deficient in Parkinson’s disease

Question 12

Serotonin

Answer 12

mood regulation, sleep, appetite, nausea, migraine
headaches

Question 13

GABA (g-aminobutyric acid)

Answer 13

• Main inhibitory NT in the brain
• Helps to regulate sleep/wakefulness
• Alcohol increases
  dampening effect → impaired motor coordination

Question 14

Glutamate

Answer 14

• Involved in learning and memory

Question 15

Neuropeptides

Answer 15

Substance P
Endorphins

Question 16

Substance P

Answer 16

• Stimulates peripheral
  nociceptors
• Mediates pain transmission to the CNS

Question 17

Endorphins

Answer 17

• Inhibits perception of pain in the CNS
• Natural opiates