Serotonin Drugs

Question 1

What is the Cardiovascular action of 5-HT2 receptors?

Answer 1

Direct vasoconstriction of vascular smooth muscle
this action also occurs with 5-HT1B/D
Platelet aggregation

Question 2

What is the Cardiovascular actions of 5-HT1 receptors?

Answer 2

Indirect vasodilation of vascular smooth muscle:

• On Pre-synaptic 5-HT1 receptors, serotonin inhibits NE
• On Endothelial cells 5-HT1 receptors, serotonin promotes release of NO and prostaglandins

Question 3

What are the Cardiovascular actions of 5-HT3 receptors?

Answer 3

Bezold-Jarisch Reflex=Reflex Bradycardia d/t stimulation of sensory nerve endings resulting in:

• inhibition of SNS
• increased vagus nerve activity

Question 4

Ketanserin

1) Use
2) Mechanism of Action

Answer 4

1)HTN Not used in US
2)5-HT2 receptor selective antagonist (5-HT2A>5-HT2C)
Blocks 5-HT2 and Alpha1 adrenergic receptors on Vascular smooth muscle

Question 5

Ergonovine

1) Use
2) Mechanism of Action

Answer 5

1) Diagnostic Tool for vasospastic angina, Control Post-partum hemorrhage
2) 5-HT2 receptor partial agonist and antagonist-causes vascular smooth muscle constriction

Question 6

Ergotamine

1) Use
2) Mechanism of Action

Answer 6

1) Acute Migraines

2) 5-HT1/2 receptor partial agonist-causes vascular smooth muscle constriction

Question 7

Sumatriptan

1) Use
2) Mechanism of Action
3) Adverse effects

Answer 7

1) Acute Migraines, Cluster HAs
2) 5-HT1B/D/F receptor agonists-causes vasoconstriction via 2 mechanisms:
- Activation of pre-junctional 5-HT1B/D receptors on sensory nerves resulting in the blockage inflammatory peptides like CGRP
- Activation of 5-HT1B/D receptors on cranial blood vessels
3) Coronary spasms in patient w/CV disease

Question 8

Zolmitriptan

1) Use
2) Mechanism of Action
3) Adverse effects

Answer 8

1) Acute Migraines, Cluster HAs
2) 5-HT1B/D/F receptor agonists-causes vasoconstriction via 2 mechanisms:
- Activation of pre-junctional 5-HT1B/D receptors on sensory nerves resulting in the blockage inflammatory peptides like CGRP
- Activation of 5-HT1B/D receptors on cranial blood vessels
* Longer Half-life than Sumatriptan*
3) Coronary spasms in patient w/CV disease

Question 9

Rizatriptan

1) Use
2) Mechanism of Action
3) Adverse effects

Answer 9

1) Acute Migraines, Cluster HAs
2) 5-HT1B/D/F receptor agonists-causes vasoconstriction via 2 mechanisms:
- Activation of pre-junctional 5-HT1B/D receptors on sensory nerves resulting in the blockage inflammatory peptides like CGRP
- Activation of 5-HT1B/D receptors on cranial blood vessels
3) Coronary spasms in patient w/CV disease