Fugu

In the Far Eastern seas there lives a fish tetragon. In Japan, this fish is known as fugu and is considered a delicacy. Her always open mouth is armed with four teeth, similar to chisels. Nevertheless, the meat of some fugu species contains a deadly poison. Therefore in Japan they say that everyone who eats fugue, as if pulling a lottery ticket "to be or not to be". Fugu is considered a delicacy, it is used to "tickle your nerves." There is even a saying: "If you want to eat fish fugu, write first testament." And this is so: many fugue fans pay their lives for this every year. Therefore, there is a law in the country that prohibits the free sale of this dangerous fish. Each cook, who is allowed to cook with fugu, must have a diploma on the completion of special courses. At the "state examination", each graduate of these courses, in the presence of the examination board and observers, should eat several dishes with fugu, which he personally cooked.

But all preventive measures do not always justify themselves. It is known, for example, that in 1947, in one such specialized restaurant, 470 people were poisoned and died, who ate food prepared with fugu.

Scientists were lucky enough to get a chemically pure fugu fish poison, which they called tetradoxine. It became known that he acts with the same force as the South American curare. Fish fugu contains a lethal dose of tetrodotoxin in the internal organs, mainly in the liver and caviar, gall bladder and skin. The liver and caviar of fish fugu can not be eaten at all, the rest of the body - after careful special treatment. The poison reversibly blocks the sodium channels of nerve cell membranes, paralyzes muscles and causes respiratory arrest.

Small doses of tetradoxine are widely used in Japanese medicine as an effective remedy against pain. Currently, there is an opportunity to grow a fugu fish that does not contain poison. Studies have shown that fish fugu is not capable of producing a neurotoxin, but only accumulates it in its body. Initially, tetrodotoxin is produced by marine bacteria, which are then consumed by a variety of living organisms.