Neuromuscular Pharmacology Flashcards
What is the mnemonic for s/s of potentially lethal poison exposures (organophosphates) on nicotinic receptors?
MATCH
M- muscle weakness, fasiculations
A- adrenal medulla activity increased
T- tachycardia
C- cramping of skeletal muscles
H- hypertension
What is Pralidoxime?
an antidote for organophosphate poisoning (but NOT against carbamate-type inhibitors like neostigmine)
What is pancuronium?
a NMJ blocker- paralyzes respiratory muscles
What is the mnemonic for s/s of potentially lethal poison exposures (organophosphates) on muscarinic receptors?
DUMBBELLS
D- defecation
U- urination
M- miosis
B- bradycardia
B- bronchospasm, bronchorrhea
E- emesis
L- lacrimation
S- salivation
____ and _____ are used to overcome poisoning by nondepolarizing agents but they would worsen NMJ blockade by succinylcholine.
Edrophonium and neostigmine
Name an agonist to the Nm receptor.
succinylcholine
Name an AChE inhibitor.
- neostigmine
- nerve gas
This blocks the release of GABA, causing failure of motor reflex inhibition–> excessive contractions occur .
tetanus toxin
What can block voltage-gated sodium channels?
lidocaine
Black widow spider venom forms pores allowing _____.
excessive Ca++ influx, clumping of vesicles, and explosive ACh release
What do these s/s indicate?
MATCH
M- muscle weakness, fasiculations
A- adrenal medulla activity increased
T- tachycardia
C- cramping of skeletal muscles
H- hypertension
potentially lethal poison exposures (organophosphates) on nicotinic receptors
Name 2 cholinesterase inhibitors.
- AChE
- BuChE
Name something that increases vesicular ACh release.
increased Ca++
_____ is lysed by tetanus toxin after the toxin has been transported in retrograde fashion to the spinal cord.
Synaptobrevin
Synaptobrevin is lysed by ______ at the NMJ to prevent vesicle fusion and ACh release, producing flaccid paralysis.
botulinum toxin
This is an Nm receptor agonist that opens the channel and allows depolarization but not repolarization –> produces flaccid paralysis.
succinylcholine
How does succinylcholine work?
it’s an Nm receptor agonist that opens the channel and allows depolarization but not repolarization –> produces flaccid paralysis
Edrophonium and neostigmine are used to overcome poisoning by nondepolarizing agents but they would worsen _______.
NMJ blockade by succinylcholine
This is a NMJ blocker that paralyzes respiratory muscles.
pancuronium
AP depolarization opens ______, allowing ____ influx.
voltage-gated Ca++ channels; Ca++
Name 2 inhibitors of vesicular ACh release.
- hemicholinum
- botulinum toxin
What is lidocaine used for?
blocking voltage-gated Na+ channels
Synaptobrevin is lysed by botulinum toxin at the NMJ to prevent vesicle fusion and ACh release, producing ______.
flaccid paralysis
Synaptobrevin is lysed by _____ after the toxin has been transported in retrograde fashion to the spinal cord.
tetanus toxin
The AP depolarization is mediated via Na+ ion inward current through ____.
voltage-gated sodium channels
What is the effect of Botox?
decreased ACh release
_____ forms pores allowing excessive Ca++ influx, clumping of vesicles, and explosive ACh release.
Black widow spider venom
This is an Nm receptor antagonist that blocks channel opening and depolarization to produce flaccid paralysis.
curare
What do these s/s indicate?
DUMBBELLS
D- defecation
U- urination
M- miosis
B- bradycardia
B- bronchospasm, bronchorrhea
E- emesis
L- lacrimation
S- salivation
potentially lethal poison exposures (organophosphates) on muscarinic receptors
Edrophonium and neostigmine are used to overcome ______ but they would worsen NMJ blockade by succinylcholine.
poisoning by nondepolarizing agents
Name 3 antidotes for organophosphate poisoning.
- Pralidoxime (but NOT against carbamate-type inhibitors like neostigmine)
- atropine
- diazepam
Name a competitive antagonist to the Nm receptor.
curare
Synaptobrevin is lysed by botulinum toxiin at the NMJ to prevent _______, producing flaccid paralysis.
vesicle fusion and ACh release
Name 2 inhibitors of depolarization.
- curare
- snake alpha-toxins
How does curare work?
it’s an Nm receptor antagonist that blocks channel opening and depolarization to produce flaccid paralysis
What is the initial sign of organophosphate poinsoning?
muscarinic excess with double vision
Name a inhibitor of muscle contraction.
dantrolene
How does tetanus toxin work?
it blocks the release of GABA, causing failure of motor reflex inhibition and excessive contractions occur
