Chapter 6 - Neurotransmitters and Their Receptors

Question 1

The two major categories of neurotransmitters are..

Answer 1

Small-molecule neurotransmitters and neuropeptides.

Question 2

What are the major groups of small-molecule neurotransmitters?

Answer 2

1. Acetylcholine
2. Amino acids
3. Purines
4. Biogenic amines

Question 3

Mention some amino acid neurotransmitters.

Answer 3

1. Glutamate
2. Aspartate
3. GABA
4. Glycine

Question 4

Mention a purine neurotransmitter.

Answer 4

ATP

Question 5

Biogenic amines is a group of small-molecule neurotransmitters. It has subgroups. What are they?

Answer 5

1. Catecholamines
2. Indoleamine
3. Imidazoleamine

Question 6

Mention three catecholamines.

Answer 6

1. Dopamine
2. Norepinephrine
3. Epinephrine

Question 7

Mention an indoleamine.

Answer 7

Serotonin (5-HT)

Question 8

Mention an imidazoleamine.

Answer 8

Histamine.

Question 9

What category neurotransmitter is Epinephrine?

Answer 9

Small molecule neurotransmitters, Biogenic amines, Catecholamines.

Question 10

What category neurotransmitter is ATP?

Answer 10

Small molecule neurotransmitters, Purines

Question 11

What category neurotransmitter is Aspartate?

Answer 11

Small molecule neurotransmitter, Amino Acids

Question 12

What category neurotransmitter is Acetylcholine?

Answer 12

Small molecule neurotransmitter.

Question 13

What category neurotransmitter is Dopamine?

Answer 13

Small molecule neurotransmitters, Biogenic amines, Catecholamines.

Question 14

What category neurotransmitter is Histamine?

Answer 14

Small molecule neurotransmitters, Biogenic amines, Imidazoleamine.

Question 15

What category neurotransmitter is Glutamate?

Answer 15

Small molecule neurotransmitters, Amino Acids.

Question 16

What category neurotransmitter is GABA?

Answer 16

Small molecule neurotransmitters, Amino Acids

Question 17

What category neurotransmitter is Norepinephrine?

Answer 17

Small molecule neurotransmitters, Biogenic amines, Catecholamines.

Question 18

What category neurotransmitter is Glycine?

Answer 18

Small molecule neurotransmitters, Amino Acids.

Question 19

All the glutamate receptors (AMPA, NMDA and kainate) are ionotropic receptors, but the NMDA receptor works slightly differently. NMDA receptors pass cations only when then postsynaptic membrane potential is depolarised, such as during activation of strong excitatory inputs and/or during action potential firing in the postsynaptic cell. What makes the NMDA receptor able to do this?

Answer 19

The NMDA receptor is blocked by Mg2+ at hyperpolarized membrane potentials, while depolarisation pushes Mg2+ out of the pore. This imparts a peculiar voltage dependence to current flow through the receptor.

Question 20

What is/are the major excitatory neurotransmitter(s) in the brain?

Answer 20

Glutamate.

Question 21

What is/are the major inhibitory neurotransmitter(s) in the brain?

Answer 21

GABA and glycine.

Question 22

What’s a functional difference between the small-molecule transmitters and the neuropeptides?

Answer 22

The actions of the small-molecule neurotransmitters are typically faster than those of the neuropeptides.

Question 23

Two types of neurotransmitter receptors. They are.

Answer 23

Ionotropic and metabotropic.

Question 24

What’s a metabotropic receptor?

Answer 24

Metabotropic receptors regulate the activity of postsynaptic ion channels indirectly, usually via G-proteins, and induce slower and longer-lasting electrical responses.

Question 25

What’s a ionotropic receptor?

Answer 25

Ionotropic or ligand-gated ion channels combine the neurotransmitter receptor and ion channel in one molecular entity, and therefore give rise to rapid postsynaptic electrical responses.