Cholinergics + adrenergic transmission and it’s presynaptic modifications

Question 1

Botulinum toxin

Answer 1

Metabolizes SNAP-25 protein, syntaxin, and synaptobrevin (vesicle associated protein)
Inhibits the release of acetylcholine
Used against spasms + cosmetically
It is a spasmolytic

Question 2

Levodopa + carbidopa

Answer 2

Levodopa: Used for Parkinson’s disease (tremors,stiffness), dystonia
Precursor of dopamine, crosses BBB and is converted to dopamine
Usually taken orally
Side effects: nausea, dizziness, orthostatic hypotension
Carbidopa: commonly used in combination with levodopa
It prevents levodopa from being converted to dopamine outside of the brain allowing for more levodopa to reach the brain
This increases efficacy and reduces side effects

Question 3

Tetrabenazin

Answer 3

Inhibits vesicular monoamine transporter (VMAT)
This leads to the decrease in storage and release of monoamines, especially dopamine
Used in huntingtons disease and tardrive dyskinesia
Helps reduce involuntary movements
Can cause depression, anxiety, and sedation