Tubo curare

Curare is the name given to the South American arrow poisons prepared from extracts of local plants by Indian tribes who dwell on the borders of Brazil, Peru, and Ecuador about the waters of the upper Amazon. The various curares are designated according to the containers into which they are packed. Tubo-curare, a dark red resinous mass is put into bamboo tubes, calabash-curare is packed in the gourd, and the pot-curare is brought to the market packed in tinted earthenware pots. The composition of the curare has been studied for a long time, but the amorphous nature of the constituents and the rarity of the crude native preparations have delayed progress in this field. 

Many indigenous groups in the South American rain forests of the Amzon basin use blowguns with blowpipe darts poisoned at the tip to paralyze hunted game. The poisonous material is known as curare (which means poison in several local languages). There are three kinds of curare which are named by the difference in the containers used to carry them these are (1) tubo curare (tube of bamboo curare), (2) pot curare, and (3) calabash curare, and are described below. 

The earliest available preparations, made as infusions and concentrated to a syrup by the native people, were designated as calabash (gourd), tubo- (bamboo), or pot (clay pot) curare depending upon the containers in which the drug was packaged. Curare is obtained from the upper regions of the Amazon river, the Orinoco basin, and the eastern slopes of the Ecuadorian plateau. The term curare is derived from the Indian name (woorari, urari) for poison (Grollman, 1962). 

Experiments in chick embryos have shown that D-tubo-curarine can cause retardation of bone growth (30) and that malformations can be produced by in utero curarization (31). Long-term curarization during pregnancy is undesirable. 

Edrophonium is an anticholinesterase muscle stimulant that facihtates myoneural junction impulse transmission by inhibiting acetylcholine destmction by cholinesterase. It is indicated in differential diagnosis of myasthenia gravis as an adjunct in evaluating treatment of myasthenia gravis in evaluation of aner-gency treatment of myasthenic aises in reversal of neuromuscular blockade by curare gallamine or tubo-curarine and in treatment of respiratory depression caused by curare overdose. 

Toxiferine I is the most physiologically active alkaloid knoAAm and has a nearly constant potency in all species. It paralyzes frogs, mice, rabbits, cats, and dogs in doses of 0.003 to 0.009 mg./kg. it is at least 15 to 30 times as potent as d-tubocurarine. Toxiferine VI and toxiferine XI are also potent curarizing agents with about 20 times the actiAuty of d-tubo-curarine in the rabbit head-drop test. 

In 1939 King (123) obtained both the leaves and liana of the plant amphi huasa (poison rope) which is used by the Indians near Tarapoto in northern Peru for the preparation of curare. It was identified as Chondrodendron tomentosum, and chemical examination showed that it contained Z-curine (Z-bebeerine) and Z-tubocurarine chloride and not d-tubo-curarine chloride as expected. However Wintersteiner and Dutcher (81)... 

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