Mode of action of ciguatera toxins

Abstract

Ciguatera fish poisoning involves one principal toxin, named ciguatoxin (1) and several secondary toxins including maitotoxin (2) and scaritoxin (3), which frequently coexist with ciguatoxin in marine organisms. All these toxins have a strong lethal potency on mice (4-8). Many pharmacological studies concern ciguatoxin, the chief pathogenic compound. Scarcer are the data about scaritoxin, a toxin specific of parrot fishes, while the mode of action of maitotoxin is actually the purpose of a deep research. This review summarizes the present knowledge. Ciguatoxin The first report on the pharmacological action of ciguatoxin was by Li (9), he observed in the anaesthetized rat a biphasic cardiovascular response with bradycardia and hypotension followed by tachycardia and hypertension. These biphasic effects resembled those of typical anticholinesterase poisons. In in vitro experiments with rabbit intestinal segments, Li observed that ciguatoxin extracts produced a marked inhibition of human and bovine erythrocyte cholinesterases. He concluded that the

Part of CIRS Nexus · Curated by Lauren Lowenstein, The Biotoxin Lady