ABSTRACT
Mechanism of Action Botox is a neurotoxin derived from the bacteria, Clostridium botulinum. It blocks
neuromuscular transmission through a three-step process. First, the toxin binds to presynaptic cholinergic motor nerve terminals. Next, the toxin is internalized into the nerve terminal by endocytosis, where it eventually enters the cytoplasm. Finally, Botox inhibits acetylcholine release by cleaving a cytoplasmic protein. The end re sult is that the muscle contraction is inhibited. However, Botox’s action is not per manent because collateral axonal sprouting establishes new neuromuscular junctions, restoring muscle function.
