INTRODUCTION Tetrodotoxin (Figure 1) is a naturally occurring compound isolated from the liver and ovaries of puffer fish. Due to its potent toxicity as a selective blocker of voltage-gated Na ion channels and the high regard for puffer fish as a culinary delicacy, tetrodotoxin has become a molecule of general, as well as scientific, interest. Structural determination revealed a densely functio...

peaked positive chronotropic responses, i.e., rapidly induced initial acceleration followed by slowly induced but long-lasting one. The initial positive response to caffeine was hardly suppressd by either adrenergic beta-blocking agents, H 56/28 (alprenolol) and propranolol, or tetrodotoxin. On the contrary, the secondary positive chronotropic response was effectively inhibited by either adrene...

Voltage clamp measurements on squid giant axons show that externally applied puffer fish poison, tetrodotoxin, eliminates only the initial inward current component of spike electrogenesis and does not affect the subsequent outward current. The selective effect on Na activation, which is reversible, confirms the view that the movements of Na and K during spike electrogenesis occur at structurall...

IIJIMA, T., MOTOMURA, S., TAIRA, N. and HASHIMOTO, K. Effects on A-V Conduction of Tetrodotoxin Selectively Injected into the A-V Node Artery of the Dog. Tohoku J. exp. Med., 1972, 107 (1), 99-100 „Ÿ Tetrodotoxin was injected selectively into the A-V node artery of the dog heart in situ, of which both vagi and both cardiac nerves were cut. Tetrodotoxin at doses of 1 to 3 μg abolished effects of...

A simple and rapid method was developed for the analysis of tetrodotoxin in puffer-fish tissues, and in serum and urine of humans poisoned after consuming puffer-fish, by means of high-performance liquid chromatography with tandem mass spectrometry (LC/MS/MS). Tetrodotoxin was extracted with 2% acetic acid. The extracted solution from puffer-fish tissues was diluted with water, and the extracte...