Curare

A brown-black poison used by South American Indians as an arrow poison.
(1) Strychnos genus of the Buddleaceae family,
(2) Plants of the genus Chondodendron , family Chondodendron;
(3) It is a resinous extract obtained from plants of the genus Nectandra of the Lauraceae family. Storage methods vary depending on the region, and there are three types, each derived from slightly different plants.
(i) Tube curare: Found in the Amazon River basin in Brazil and Peru, its original plants are (2) and (3).
(ii) Pot curare: It is mainly found in the upper reaches of the Orinoco River in Venezuela. Its toxicity is relatively low. The original plant is (2).
(iii) Calabash curare: Found in French Guiana, Venezuela, Colombia, etc. It is the most poisonous and its original plant is (1).
All of the ingredients are complex, water-soluble quaternary ammonium bases called curare alkaloids, which are the main source of action. The ingredients vary depending on the type, and many are known, including d -bocurarine, which is obtained from bamboo tube curare, as well as curarine, toxiferine, and caracurine. Cattle curare has a large number of ingredients, including bis-indole compounds formed by the condensation of two molecules of indole derivatives, and is highly varied, making it one of the most chemically complex. The site of action of curare alkaloids is not the central nervous system, but blocking the neuromuscular junction, and they are unique in that they have a paralyzing effect at the junction between motor nerves and voluntary muscles. Tubocurarine is used as an anesthesia for muscle relaxation during surgical operations.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

南米インディアンが矢毒として使用する黒褐色の毒物．
(1)フジウツギ科Strychnos属植物，
(2)ツヅラフジ科Chondodendron属植物，
(3)クスノキ科Nectandra属植物
などから得られる樹脂状抽出物である．地方により貯蔵法が違い，次の3種類があり，原植物もやや異なる．
(ⅰ)竹筒クラーレ(tube curare)：ブラジル，ペルーのアマゾン川流域に産し，原植物は(2)および(3)．
(ⅱ)ツボクラーレ(pot curare)：主産地はベネズエラのオリノコ川上流地域．毒性は比較的弱い．原植物は(2)．
(ⅲ)ヒョウタンクラーレ(calabash curare)：フランス領ギアナ，ベネズエラ，コロンビアなどに産する．もっとも毒性が強く，原植物は(1)．
成分はいずれもクラーレアルカロイドとよばれる複雑な水溶性の第四級アンモニウム塩基で，これが作用の本体をなしている．種類によって成分が異なり，竹筒クラーレより得られるd-ボクラリンをはじめ，クラリン，トキシフェリン，カラクリンなど多くが知られている．ヒョウタンクラーレの成分はその数が多く，インドール誘導体が二分子縮合したビスインドール型化合物を含み，変化に富んでいるので，化学的にもっとも複雑なものに属している．クラーレアルカロイドの作用部位は中枢神経ではなく，神経-筋接合部の遮断にあり，運動神経と随意筋の接合部に麻ひ作用をもつ特異なものである．ツボクラリンは，外科手術における麻酔に筋弛緩の目的で用いられる．

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