Neurotransmission & ANS Pharmacology III: Other Mediators: Amines, Peptides, Eicosanoids, & NO Flashcards
What precursor is Serotonin synthesised from?
L-Tryptophan
What receptors does Serotonin act via?
5-HT receptors
TRUE OR FALSE:
5-HT receptors are structurally similar to adrenoceptors?
True.
Therefore, cross-effects of drugs
Which drug acts on the 5-HT1D receptor?
- Sumpatripan
- Used to treat migraines
- Agonist
Which drug acts on the 5-HT2A receptor?
- Psychedelic drugs e.g. LSD
- Agonist
Which drug acts on the 5-HT3 receptor?
- Ondansetron
- Used to control nausea / vomiting
- Antagonist
What precursor is Histamine synthesised from?
L-histidine
Where is Histamine stored?
Granules within mast cells and basophils
Which Histamine receptor type is found on bronchial smooth muscle, ileum, and endothelial cells?
H1
Which Histamine receptor type is found on gastric parietal cells, uterine smooth muscle, vascular smooth muscle, and heart?
H2
Which Histamine receptor type is found in the CNS?
H3
What are the FIVE Opioid Peptide Receptors?
- μ (mu)
- δ (delta)
- κ (kappa)
- ORL1(nociceptive)
- ζ (zeta)
Are Opioid Receptors ion channels or GPCRs?
Gi / G0 coupled
What are TWO examples of Tachykinins?
- Substance P
- Neurokinins A & B
Which receptors do Tachykinins act via?
G-protein coupled NK1, NK2 & NK3 receptors
What is an example of a Bradykinin?
9-mer neuropeptide
Which receptors do Bradykinins act via?
B1 & B2 receptors
What happens when Bradykinins act on a receptor?
GPCRs activate phospholipase A2 that leads to prostaglandin synthesis
TRUE OR FALSE:
Eicosanoids are pre-synthesised and stored?
False.
They are made ‘on demand’
What type of structure do Prostaglandins have?
5-member ring structure
What receptors do Prostaglandins act via?
G-protein coupled prostanoid receptors
What type of structure do Thromboxanes have?
6-member ring structure
What receptors do Thromboxanes act via?
Prostanoid receptors
What is the structure of Leukotrienes?
Straight chain, 3 conjugated double bonds
What receptors do Leukotrienes act via?
G-protein coupled leukotriene (LT) receptors
What are Endocannabinoids derivatives of?
Arachidonic acid
Where are Endocannabinoid CB1 receptors located?
Brain
Where are Endocannabinoid CB2 receptors located?
Immune system
What types of receptors are Endocannabinoid CB1 & CB2 receptors?
GPCRs
* coupled via G1 (decreases cAMP) and G0 (opens K+ channels)
Which enzyme does Nitric Oxide activate?
Guanylyl Cyclase to cGMP
Apart from NO, what TWO other gases have signalling roles?
CO & H2S
What are THREE characteristics of gases with signalling roles?
- Synthesised by enzymes, then diffuse 3D
- Target protein haeme groups or redox-active amino acids
- Short-lived, so are generated as needed
