💆🏼♂️ Flashcards
agonists and antagonists are drugs that…
act directly on the receptors
agonists are _____ (3) which bind to specific receptors and initiate a ______ in the receptor resulting in a biological response
drugs, hormones, or transmitters
conformational change
affinity (def.)
ability of agonists to bind to receptors
efficacy (def.)
ability of agonist, once bound to a receptor, to initiate a biological response
block caused by competitive antagonist can be reversed by…
🔼 the agonist concentration
synapses are classified according to…
the transmitter released from the presynaptic neurone
synapses where the presynaptic neurone produces and relates acetylcholine (ACh) transmission is classified as…
cholinergic
Receptors to which ACh binds are called…
cholinoreceptors
two classes of of cholinoreceptors are:
- nicotinic cholinoceptors (nAChRs)
- muscarinic cholinoceptors
nicotinic cholinoceptors (nAChRs) are activated/ not activated by:
ACh
nicotine (tobacco alkaloid)
muscarine 🍄 (fungal alkaloid)
✅ (activated by) ACh
✅ nicotine (tobacco alkaloid)
❌ muscarine 🍄 (fungal alkaloid)
muscarinic cholinoceptors are activated/ not activated by:
ACh
muscarine 🍄
nicotine
✅ ACh
✅ muscarine 🍄
❌ nicotine
⍺-bungarotoxin comes from a _____
it binds specifically to the _____ receptors
_____ muscles get _____
snake
nicotinic
skeletal
paralysed
MEPP is…
MINIATURE END PLATE POTENTIAL
MEPPs summate to give ____ which, initiates _____ —> _______ (body reaction)
an end plate potential (EPP)
an action potential
muscle contraction
_______ synthesises ACh from precursors _____ and ______ from _____ (location)
Choline acetyl transferase (CAT)
choline
Acetyl Coenzyme A (Acetyl Co-A)
mitochondria
Reuptake of choline is _____ (ion) dependent & blocked competitively by _______ (not used clinically).
Amplitude of the EPP & the MEPP are ______ i.e. _______ (🔼/no change/🔽) in the quantal content.
Na+
hemicholinium 3
🔽
no change
Transport of ACh into vesicles can be blocked by inhibition of the ACh transporter by _____
Amplitude of the EPP & the MEPP are ______ i.e. _______ (🔼/no change/🔽) in the quantal content.
VESAMICOL
🔽
no change
________ (type of toxin) blocks Na+ channels (_______ [why is it working?]).
who produces?
Tetrodotoxin (TTX)
no AP = no release
puffer fish 🐡
________ (type of toxin) block voltage-gated Ca2+ channels (_______ [why is it working?]).
The EPP amplitude _______ (🔼/no change/🔽)
_______ (🔼/no change/🔽) in the MEPP amplitude.
_______ (🔼/no change/🔽) quantal content
who produces?
conotoxins 🔽 Ca2+ influx = 🔽 release 🔽 no change 🔽 cone snail🐚
________ (type of toxin) blocks voltage-gated K+ channels, as (_______ [why is it working?]).
EPP amplitude _______ (🔼/no change/🔽)
_______ (🔼/no change/🔽) in the MEPP amplitude
_______ (🔼/no change/🔽) quantal content
who produces?
Dendrotoxin prolonged action potential —> 🔼Ca2+ influx —> 🔼 release 🔼 no change 🔼 eastern green mamba🐍
________ (type of toxin) blocks vesicle fusion = no release
EPP amplitude _______ (🔼/no change/🔽)
_______ (🔼/no change/🔽) in the MEPP amplitude
_______ (🔼/no change/🔽) quantal content
where can be found?
Botulinum toxin 🔽 no change 🔽 botox💉
________ (type of toxin)
when toxin administered: massive ACh release, muscle spasms
afterwards: depletion of vesicles, inhibition of endocytosis, distended terminal paralysis
where can be found?
⍺-latrotoxin
black widow🕷
