Pathophysiology thumb|upright=1.4|A neurotransmitter-filled vesicle before and after exposure to the tetanus toxin. The cleavage of the VAMP protein by the toxin inhibits vesicle fusion and neurotransmitter release into the synapse. Tetanus neurotoxin (TeNT) binds to the presynaptic membrane of the neuromuscular junction, is internalized, and is transported back through the axon until it reaches the central nervous system. Here, it selectively binds to and is transported into inhibitory neurons via endocytosis. It then leaves the vesicle for the neuron cytosol, where it cleaves vesicle associated membrane protein (VAMP) synaptobrevin, which is necessary for membrane fusion of small synaptic vesicles (SSV's). SSV's carry neurotransmitter to the membrane for release, so inhibition of this process blocks neurotransmitter release.
Pathophysiology thumb|upright=1.4|A neurotransmitter-filled vesicle before and after exposure to the tetanus toxin. The cleavage of the VAMP protein by the toxin inhibits vesicle fusion and neurotransmitter release into the synapse. Tetanus neurotoxin (TeNT) binds to the presynaptic membrane of the neuromuscular junction, is internalized, and is transported back through the axon until it reaches the central nervous system. Here, it selectively binds to and is transported into inhibitory neurons via endocytosis. It then leaves the vesicle for the neuron cytosol, where it cleaves vesicle associated membrane protein (VAMP) synaptobrevin, which is necessary for membrane fusion of small synaptic vesicles (SSV's). SSV's carry neurotransmitter to the membrane for release, so inhibition of this process blocks neurotransmitter release.