Mechanism action of botulinum toxin ?
Ans. is 'c' i.e., Inhibition of acetylcholine release Botulinum Toxin Cl. botulinum produces a powerful exotoxin that is responsible for its pathogenicity. The toxin differs from other exotoxins in that it is not released during the life of organism. It is produced intracellularly and appears in the medium only on the death and autolysis of the cell. It is the most toxic substance known. Toxin is heat labile, but spores are highly heat resistant. It acts by blocking the release of acetylcholine at synapses and neuromuscular junction. It acts presynaptically. Toxin of all types (A, B, C, D, E, F, G) are neurotoxin except C2 which is a cytotoxin (enterotoxin).
Increased cAMP
Increased cGMP
Inhibition of acetylcholine release
Inhibition of noradrenaline release