Tetrodotoxin from Marine Puffer Fish and their Biomedical Application

Tetrodotoxin (TTX) is the best known marine toxin because of its frequent involvement in fatal food poisoning, unique chemical structure and specific action of blocking sodium channels of excitable membranes. Tetrodotoxin is a powerful neurotoxin that can cause death early in 60 % of the humans. Human only has to ingest a few milligrams for a fatal reaction to the toxin to occur. Once consumed the toxin blocks the sodium channels in the nerve tissues, ultimately paralyzing the muscle tissue. Curiously, the toxin seems to be synthesised by the fish itself, but by bacteria associated with the fish. The fish has a mutation in its own sodium channels, which makes it resistant to the effect of the toxin.