Serotonin Receptors Overview

Question 1

What does the 1A receptor do?

Answer 1

Opens K+ channel to hyper polarize the neuron

Question 2

What do the 1B/1D receptors do?

Answer 2

Prevent release of the neurotransmitters

Question 3

Which receptor works on the Phosphatadyl Inositol system (inc DAG, protein kinase C, IP3) to release stored calcium?

Answer 3

2

Question 4

What is the main action of the 5HT receptors?

Answer 4

Contract arteries (especially carotid)

Question 5

What is different about the blood vessels that 5HT-1 and 5HT-2 contract?

Answer 5

The 1 contracts cerebral blood vessels (1B - reduce migraines)
The 2 contracts other blood vessels

Question 6

What are the main actions of the 2 receptor?

Answer 6

1 - Other blood vessel contraction
2 - Intestinal smooth muscle contraction
3 - Dilates heart muscle (inc NO, prostaglandins, permeability, microcirculation)
4 - Increases platelet aggregation (2A)
5 - Contracts stomach fundus (2B)

Question 7

What are the main actions of the 3 receptor?

Answer 7

• Bradycardia
• Reflex hypotension
• Vomiting

Question 8

What are the main actions of the 4 receptor?

Answer 8

Peristalsis and secretion in the GI

Question 9

Which receptor increases and which decreases cAMP?

Answer 9

4 Increases

1 Decreases

Question 10

Which receptors are auto and hetero receptors?

Answer 10

1B/1D

Question 11

Which drug blocks 1A?

Answer 11

Busiprone

Question 12

Which drugs activate the 1B/1D?

Answer 12

Triptans

Question 13

Which receptor is in the brain as an inhibitory pre-synaptic receptor?

Answer 13

1

Question 14

Which receptor is a serotonin gated sodium channel?

Answer 14

3

Question 15

Which receptor is found in baroreceptors, chemoreceptors, and the CTZ?

Answer 15

3