what happens in the presence of botulinum toxin
Botulism Clostridium botulinum is an anaerobic, Gram positive, spore-forming rod. Botulinum toxin is one of the most powerful known toxins: about one microgram is lethal to humans when inhaled.[14] It acts by blocking nerve function (neuromuscular blockade) through inhibition of the excitatory neurotransmitter acetylcholine's release from the presynaptic membrane of neuromuscular junctions in the somatic nervous system. This causes paralysis. Advanced botulism can cause respiratory failure by paralysing the muscles of the chest; this can progress to respiratory arrest.[15] Furthermore, acetylcholine release from the presynaptic membranes of muscarinic nerve synapses is blocked. This can lead to a variety of autonomic signs and symptoms described above.