The toxin involved is called tetrodotoxin and was originally believed to be a true ichthyosarcotoxin produced by the fish itself. Puffer fish, the most common source of tetrodotoxin, is eaten as the delicacy fugu in some Southeast Asian countries.
Although tetrodotoxin is concentrated in the fish’s skin and internal organs, all parts of the fish may contain it. Most poisonings occur in Japan, where sushi chefs must be licensed in the proper technique of preparing puffer fish owing to risk of death with improper preparation.
Tetrodotoxin blocks the action potentials in nerves by binding to the pores of the voltage-gated, fast sodium channels in nerve cell membrane.
The symptoms of puffer fish poisoning are similar to those described for paralytic shellfish poisoning, including initial tingling and numbness of lips, tongue and fingers leading to paralysis of the extremities; ataxia,; difficulty on speaking; and finally death buy asphyxiation due to respiratory paralysis. Nausea and vomiting are common early symptoms.
Tetrodotoxin of puffer fish poisoning
