Epilepsy

Question 1

What are the 4 classic drug target sites?

Answer 1

1. Receptors - eg. GABAAr, AMPAr, NMDAr
2. Enzymes - eg. GABA transaminase
3. Ion channels - eg. VGSCs, VGCCs
4. Transport proteins - eg. GABA transporter

Question 2

How does lamotrigine work to treat seizures?

Answer 2

Target:
- VGSCs (ion channel)
- Glutamergic neurones in temporal lobe

Block VGSCs in pre-s neurones —> dec pre-s n depolarisation —> dec NT release —> inhibit AP in post-s n

Question 3

How does diazepam work to treat seizures?

Answer 3

Target:
- GABAAr (receptor)
- Post-s neurones in temporal lobe

Inc GABAAr effectiveness —> inc Cl- influx —> inhibit AP in post-s neurone

Question 4

How does pregabalin work to treat seizures?

Answer 4

Target:
- VGCCs (ion channel)
- Glutamergic neurones in temporal lobe

Block VGCCs in pre-s neurones —> dec pre-s n vesicle release —> dec NT release —> inhibit AP in post-s n

Question 5

How does levetiracetam work to treat seizures?

Answer 5

Target:
- SV2A (synaptic vesicle protein)
- Glutamergic neurones in temporal lobe

Inhibit vesicle fusion in pre-s neurones —> dec NT release —> inhibit AP in post-s n

Question 6

How does sodium valproate work to treat seizures?

Answer 6

Target (non-selective):
- VGSCs
- VGCCs
- NMDAr
- GABA transaminase

Limitations:
- non-selective —> many side effects
- teratogenic —> avoid in child-bearing age females