Related Experiment Video
Updated: Aug 9, 2026

Functional Evaluation of Biological Neurotoxins in Networked Cultures of Stem Cell-derived Central Nervous System Neurons
Published on: February 5, 2015
Actions of 4-epitetrodotoxin and anhydrotetrodotoxin on the squid axon
Abstract:
The actions of the newly discovered 4-epitetrodotoxin and of anhydrotetrodotoxin have been studied on the internally perfused squid giant axon under voltage-clamped conditions. Both compounds are selective in blocking only the sodium channel. The concentration for reducing the sodium current to one-half is 13.2 nM for 4-epitetrodotoxin and 298 nM for anhydrotetrodotoxin. Compared with tetrodotoxin, the relative potencies are 0.39 for 4-epitetrodotoxin and 0.018 for anhydrotetrodotoxin. The results suggest that hydrogen bonding at C-4 and C-9 is an important contributing force in binding to the membrane receptor site.
More Related Videos
09:55Examining Monosynaptic Connections in Drosophila Using Tetrodotoxin Resistant Sodium Channels
Published on: February 14, 2018
11:04Unraveling the Role of Discrete Areas of the Rat Brain in the Regulation of Ovulation through Reversible Inactivation by Tetrodotoxin Microinjections
Published on: September 3, 2020
Related Concept Videos
Action Potentials
Resting Membrane Potential
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
Action Potential
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Action Potential
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Tetanus
Botulism