Ciguatoxin

Chemical structure of the ciguatoxin CTX1B

The ciguatoxins are a class of poisonous organic compounds found in some fish that causes ciguatera.

There are several different chemicals in this class. "CTX" is often used as an abbreviation in their names.

• PubChem 5311333 - Ciguatoxin 1
• PubChem 6441260 - Ciguatoxin 2
• PubChem 6444399 - Ciguatoxin 3
• PubChem 6450530 - Ciguatoxin 4B (also called Gambiertoxin 4b)

Toxic Effect

Ciguatoxin lowers the threshold for opening voltage-gated sodium channels in synapses of the nervous system. Opening a sodium channel causes depolarization, which could sequentially cause paralysis, heart contraction, and changing the senses of hearing and cold.

Because they do not cross the blood brain barrier (BBB), ciguatoxins solely affect the peripheral nervous system (PNS).

The major symptoms will develop within a few hours of toxin ingestion: vomiting, diarrhea, numbness of extremities, mouth and lips, reversal of hot and cold sensation, muscle and joint aches. The symptoms may last from days to weeks or even months depending on each individual situation. There is no antidote for ciguatoxin poisoning.

Bioaccumulation route

Ciguatoxin is produced by Gambierdiscus toxicus, a type of dinoflagellate, which are eaten by big coral reef fish, such as grouper, wrasse, triggerfish, lionfish, and amberjack. Ciguatoxin usually accumulates in skin, head, viscera, and roe of the fish.

Ciguatoxin cannot be destroyed by cooking.^[1] Rapid testing for this toxin in fish marketed as food is not standard.

References

1. ^ Swift A, Swift T (1993). "Ciguatera". J. Toxicol. Clin. Toxicol. 31 (1): 1–29. doi:10.3109/15563659309000371. PMID 8433404. 

External links

• MeSH Ciguatoxins