Pharmacology

Question 1

Choline acetyltransferase (ChAT)

Answer 1

Enzyme that combines ACoA and choline to form ACh.

Question 2

VAMP and SNAPs

Answer 2

Plasma membrane proteins that initiate vesicle-plasma membrane fusion.

Question 3

AChE

Answer 3

Breaks down ACh in synaptic cleft.

Question 4

Choline transporter

Answer 4

Recycles broken down choline back into the motor neuron.

Question 5

nAChR

Answer 5

Ligand gated ion channel (Na+)
Na+ increase causes muscle action potential.
Ionotropic

Question 6

mAChR

Answer 6

G-protein coupled receptor.
NOT located in skeletal muscle.
Metabotropic.

Question 7

Agents that affect the nerve AP (2)

Answer 7

Tetrodotoxin, local anesthetics.

Question 8

Tetrodotoxin MOA

Answer 8

Inhibits VG Na+ channels blocking axonal conduction.

Question 9

Agents that affect vesicular ACh release

Answer 9

Botulinum toxin and tetanus toxin

Question 10

Botulinum toxin MOA

Answer 10

Damages SNARE complex and orevents the release of ACh.

Question 11

Tetanus toxin MOA

Answer 11

Blocks fusion of synaptic vesicles by targeting synaptobrevin.
After binding to the presynaptic membrane, tetanus toxin is retroaxonally to the SC.

Question 12

Agents that affect depolarization (2)

Answer 12

Curare alkaloids and Succinylcholine

Question 13

Curare MOA (d-tubocurarine)

Answer 13

Competes w/ ACh for nAChR on MEP, decreasing the end plate potential.

Question 14

Succinylcholine MOA

Answer 14

Binds to skeletal muscle nAChR and initially causes depolarization, but then leads to receptor blockage and paralysis.

Question 15

Cholinesterase inhibitors MOA

Answer 15

Inhibit AChE to increase concentration of ACh at NMJ.

Question 16

Dantolene MOA

Answer 16

Inhibits ryanodine receptors in SR and blocks release of Ca2+.

Question 17

Sx of tetrodotoxin

Answer 17

Weakness, dizziness, generalized paralysis.

Question 18

Sx of botulism

Answer 18

Nausea, vomiting, abdominal pain, diarrhea and dry mouth.

Question 19

Sx of tetanus toxin

Answer 19

Spastic paralysis, lockjaw, autonomic overactivity.

Question 20

Curare is used:

Answer 20

During anesthesia.

Question 21

Succinylcholine is used:

Answer 21

Before anesthesia.

Question 22

Cholinesterase inhibitors are used for:

Answer 22

Dementia, Alzheimer’s disease, Parkinson’s disease, myasthenia gravis, etc.

Question 23

Dantrolene is used for:

Answer 23

Malignant hyperthermia, upper motor neuron d/o.