Quantitative analysis of toxin extracts from various tissues of wild and cultured puffer fish by an electrophysiological method

• Published in: Toxicon (Oxford) Vol. 51; no. 4; pp. 606 - 614
• Main Authors: Sasaki, Keita, Takayama, Yasunori, Tahara, Tatsuo, Anraku, Kensaku, Ito, Yushi, Akaike, Norio
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 15.03.2008; Elsevier Science
• Subjects: Animal poisons toxicology. Antivenoms; Animals; Biological and medical sciences; Electrophysiology - methods; Female; Food poisoning; Medical sciences; Neurons - drug effects; Neurons - physiology; Puffer toxin; Rats; Single CA1 neuron; Sodium channel; Sodium Channels - metabolism; Tetraodontiformes - metabolism; Tetrodotoxin; Tetrodotoxin - analysis; Tissue Extracts - chemistry; Toxicology; Wild and cultured fish; Tetrodotoxin; Wild and cultured fish; Sodium channel; Single CA1 neuron; Puffer toxin; Food poisoning; Rat; Toxicity; Rodentia; Electrophysiology; Animal origin; Ionic channel; Extract; In vitro; Tissue; Toxin; Vertebrata; Mammalia; Neuron; Animal; Pisces; Sodium ion; Digestive diseases; Quantitative analysis
• ISSN: 0041-0101; 1879-3150
• DOI: 10.1016/j.toxicon.2007.11.008

We observed the effects of the toxin extracted from various tissues of wild and cultured puffer fish on voltage-dependent sodium current ( I Na) using single rat CA1 neurons, and compared the results with that of tetrodotoxin (TTX). Toxin extracts from wild puffer fish inhibited I Na in a dilution-dependent manner, and toxin extracts from liver or ovary produced 300 times greater inhibition than that from muscle, and corresponded to about 65 μg TTX/g tissue. We also used puffer fish cultured in net cages or in tanks set up on land, in an attempt to isolate them from the food chain. The toxin extracts from cultured puffer fish also suppressed I Na, but the inhibition was much weaker, and the effects of toxin extracts were almost the same in all tissues examined including liver, ovary, muscle, etc. We calculated the maximum edible amount for each tissue, assuming that the lethal dose of TTX is 1–10 μg/kg, and we found that the liver or ovary was edible in the case of cultured puffer fish.