Question

An elderly woman received a botox injection for the treatment of wrinkles. Which of the following is the mechanism of action of botulinum toxin?

• A. Inhibits the release of acetylcholine
• B. Release of noradrenaline at synaptic cleft
• C. Selectively and irreversibly inhibits nicotinic receptors
• D. Stimulates muscarinic and nicotinic receptors

Answer 1

The Correct Option is A

Botulinum toxin, commonly known as botox, works by interfering with the neurotransmission process. Its mechanism of action involves the inhibition of acetylcholine release from presynaptic nerve terminals. This is how botulinum toxin effectively reduces muscle contraction and helps in the treatment of wrinkles.

To understand this process, consider the following detailed steps:

• Neurotransmitter Process: Normally, nerves communicate by releasing neurotransmitters, such as acetylcholine, which then bind to receptors on muscles causing them to contract.
• Action of Botulinum Toxin: Botulinum toxin enters nerve terminals and cleaves specific proteins essential for the docking and release of acetylcholine-containing vesicles.
• Result: By inhibiting acetylcholine release, botulinum toxin causes a decrease in muscle activity, effectively relaxing the muscle and reducing wrinkles.

Mechanism	Description
Botulinum Toxin	Inhibits the release of acetylcholine

Therefore, the correct option is: Inhibits the release of acetylcholine.