Some neurotoxins work essentialiy the same way as some local anesthetics, which is to prevent depolarization by blocking Na + entry into the cell only. bind to Na + channels only. nactivate the enzyme that activates the neurotransmitter onliy. bind to Na+ channels and prevent depolarization by blocking Nat entry into the cell. inactivate the enzyme that activates the neurotransmitter and bind to Na +.