epilepsy Flashcards
what are the 4 classical drug target sites
receptors
enzymes
ion channels
transport proteins
examples of receptors
GABAA receptor, AMPA receptor, NMDA receptor
examples of enzymes
GABA transaminase
examples of ion channels
voltage gated Na and Ca channel
examples of transport proteins
GABA transporter
what is the drug target for diazepam
GABAa receptor (alpha subunit)
where is the diazepam drug target
postsynaptic neurones in the temporal lobe (for complex, partial focal seizures)
what is the result of diazepam
diazepam binds and increases the effectiveness of GABA activation of this receptor (it does not activate the receptor itself) > leads to Cl- influx in the presence of GABA which hyperpolarises the temporal lobe neurone and decreases the effects observed
what are some drugs used to treat epilepsy (3)
lamotrigine
pregabalin
levetiracetam
drug target for lamotrigine
voltage gated sodium channel
drug target for pregabalin
voltage gated calcium channel
drug target for levetiracetam
synaptic vesicle protein SV2A
glutamatergic neurones in the temporal lobes
how does lamotrigine cause an antiepileptic effect
blocking the sodium channels reduces neuronal depolarisation which would eventually lead to NT release
glutamate neurotransmission is decreased and there is less excitatory stimulation of the postsynaptic neurone
how does pregabalin cause an antiepileptic effect
blocking the Ca channels prevents Ca influx into the neruone which is required to promote vesicle exocytosis and NT release
glutamate neurotransmission is decreased and there is less excitatory stimulation of the post synaptic neurone
how does levetiracetam cause an antiepileptic effect
drug interferes with vesicle fusion and therefore reduces exocytosis of glutamate > decreasing the excitatory activation of the postsynaptic neurone
