Question 21 / 27:
How do tetanus toxin and botulinum toxin interfere with synaptic transmission (explain in molecular detail)?How does one produce a rigid paralysis, while the other causes flaccid paralysis?
Toxin’s heavy and light chain required to enter cell. Light chain then freed and acts
as metalloprotease to enzymatically cleave different proteins of the SNARE complex
(required for synaptic vesicle fusion).
Tetanus tends to hit inhibitory synapses (thus rigid, due to disinhibition of
motoneuron), and botulinum toxin hits NMJs and others. (Tropism of toxin.)
