Gymnothorax

Several species of the moray eel (Gymnothorax) have caused toxic reactions, especially ki Japan. The toxic principle appears to be protekiaceous and is found predominately ki the blood but it may occur ki the flesh as well. Its exact stmcture remains somewhat uncertain. 

CTx that has been purified from muscles of Gymnothorax javanicus stimulates the release of neurotransmitters such as 7-aminobutyric acid and dopamine from rat brain nerve terminals. It causes a membrane depolarization of mouse neuroblastoma cells and, under appropriate conditions, it creates spontaneous oscillations of... 

Nakajlma and coworkers (20) reported an ether soluble extract from concavum to be slightly toxic to mice but provided little additional information. Crude fractions containing ciguatoxin obtained from moray eel (Gymnothorax javanicus) and toxlcus from the Pacific were reported to have LD q s of 12.2 mg/kg and 28.1 mg/kg, respectively (37). These compare well with the LD q of 8.3 mg/kg for similarly purified ESAF from concavum. 

Ciguatoxin (CTX) is the major chemical entity associated with ciguatera fish poisoning. CTX, a term given to the low dalton lipid by Scheuer et al. (JL) was isolated from livers of Gymnothorax obtained from an endemic area in the Pacific. A recent study by Tachibana ( 2) in Scheuer s laboratory suggests that CTX consists of numerous cyclic polyether residues similar to okadaic acid (3-5) and monensin ( ). ... 

Source of Extracted Fish Toxin. Two different extracts of ciguatoxic fish were used in this study. Partially purified ciguatoxin was derived from the liver and viscera of the Pacific moray eel (Gymnothorax Javanicus) and was a side fraction of the... 

Gymnothorax Javanicus (Bledcer, 1859)(morayeel), Osteidi., frcan French Polynesia... 

Notothenia gibberifrons Lonnberg Gymnothorax johnsoni Smith Carassius auratus (L.)... 

Moray eels Gymnothorax javanicus) have also been reported to be occasionally toxic. The symptoms resemble ciguatera but additionally often include excessive salivation. As moray eel toxicity seems most common in eels caught on coral reefs when other fish are ciguatoxic, it seems most likely that moray eel poisoning is actually ciguatoxin accumulated by this formidable predator. 

Murata, M., A.-M. Legrand, Y. Ishibashi, M. Eukui, andT. Yasumoto (1990). Structures aud coufiguratious of ciguatoxin from the moray eel Gymnothorax javanicus and its likely precursor from the diuoflagel-late Gambierdiscus toxicus. J. Am. Chem. Soc. 112,4380-4386. 

Ciguatoxin (CTX 1) (formula see below). For structural elucidation 0.35 mg of C. (CeoHaeOg, Mr 1111.33) were isolated from 125 kg intestines of the moray Gymnothorax javanicus (primary origin Gambierdiscus toxicus). CTX acts as an agonist of voltage-sensitive sodium channels (VSSC). The lethal dose is 0.35 pg/kg (mouse). Thus, the toxin is about 100 times more potent than tetrodotoxin. 

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