Curare is a drug from the alkaloid family, used in modern medicine as a skeletal muscle relaxant, often with general anesthesia for surgeries of the chest and abdomen. It is of botanical origin, from tropical American plants such as Chondrodendron and Strychnos species. Indigenous peoples of South America have long used crude curare as arrow poisons to capture wild game. Curare is a neuromuscular blocking agent that causes flaccidity in skeletal muscle by competing with acetylcholine, preventing nerve impulses from activating skeletal muscles.

From where is curare traditionally obtained?

Curare is a drug from the alkaloid family of organic compounds, whose derivatives are used in modern medicine as skeletal muscle relaxants. It is of botanical origin, and its sources include various tropical American plants, mainly Chondrodendron species and Strychnos species. Crude curare preparations have long been used as arrow poisons to aid in capturing wild game by Indigenous peoples of South America. The name curare is a European interpretation of an Indigenous word meaning "poison".

How does curare affect the human body?

Curare is a drug from a family of organic compounds called alkaloids, derived from tropical American plants. It is a neuromuscular blocking agent that causes skeletal muscle relaxation by competing with acetylcholine, a neurotransmitter, at the neuromuscular junction. This prevents nerve impulses from activating skeletal muscles, leading to profound relaxation. The relaxation begins in the muscles of the toes, ears, and eyes, progressing to the muscles of the neck and limbs, and finally to the muscles involved in respiration. In fatal doses, respiratory paralysis causes death. Curare derivatives are used in modern medicine as skeletal muscle relaxants, often administered with general anesthesia for surgeries of the chest and abdomen. Certain curare alkaloids are also used as relaxants to facilitate endotracheal intubation and to relieve muscular contractions and convulsions, such as those that occur in tetanus.

What was curare historically used for by Indigenous peoples?

Curare is a poisonous substance that comes from tropical American plants. Indigenous peoples of South America have historically used crude curare preparations as arrow poisons to aid in capturing wild game. The name curare is derived from Indigenous words meaning "poison," rendered as ourara , urali , urari , woorali , and woorar i.

How do doctors use curare or similar compounds in modern medicine?

Curare derivatives are used in modern medicine primarily as skeletal muscle relaxants, often administered with general anesthesia for surgeries of the chest and abdomen. Curare functions as a neuromuscular blocking agent, causing muscle relaxation by competing with acetylcholine at the neuromuscular junction, preventing nerve impulses from activating skeletal muscles. Though effective, curare caused hypotension, limiting its use. It has largely been replaced by curare-like drugs, including atracurium, pancuronium, and vecuronium. Certain curare alkaloids are employed as relaxants to facilitate endotracheal intubation and relieve muscular contractions and convulsions, such as those occurring in tetanus. The effects of curare alkaloids can be reversed by administering an anticholinesterase such as neostigmine, which prevents the destruction of acetylcholine at nerve endings.

curare

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Key People:: Claude Bernard; Daniel Bovet

Related Topics:: Strychnos; tubocurarine; Chondrodendron tomentosum; Strychnos toxifera; muscle relaxant

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curare

chemical compound

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What is curare?
Curare is a drug from the alkaloid family, used in modern medicine as a skeletal muscle relaxant, often with general anesthesia for surgeries of the chest and abdomen. It is of botanical origin, from tropical American plants such as Chondrodendron and Strychnos species. Indigenous peoples of South America have long used crude curare as arrow poisons to capture wild game. Curare is a neuromuscular blocking agent that causes flaccidity in skeletal muscle by competing with acetylcholine, preventing nerve impulses from activating skeletal muscles.
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From where is curare traditionally obtained?
Curare is a drug from the alkaloid family of organic compounds, whose derivatives are used in modern medicine as skeletal muscle relaxants. It is of botanical origin, and its sources include various tropical American plants, mainly Chondrodendron species and Strychnos species.

Crude curare preparations have long been used as arrow poisons to aid in capturing wild game by Indigenous peoples of South America. The name curare is a European interpretation of an Indigenous word meaning "poison".
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2. Definition of curare
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How does curare affect the human body?
Curare is a drug from a family of organic compounds called alkaloids, derived from tropical American plants. It is a neuromuscular blocking agent that causes skeletal muscle relaxation by competing with acetylcholine, a neurotransmitter, at the neuromuscular junction. This prevents nerve impulses from activating skeletal muscles, leading to profound relaxation. The relaxation begins in the muscles of the toes, ears, and eyes, progressing to the muscles of the neck and limbs, and finally to the muscles involved in respiration. In fatal doses, respiratory paralysis causes death.

Curare derivatives are used in modern medicine as skeletal muscle relaxants, often administered with general anesthesia for surgeries of the chest and abdomen. Certain curare alkaloids are also used as relaxants to facilitate endotracheal intubation and to relieve muscular contractions and convulsions, such as those that occur in tetanus.
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1. curare
2. Definition of curare
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What was curare historically used for by Indigenous peoples?
Curare is a poisonous substance that comes from tropical American plants. Indigenous peoples of South America have historically used crude curare preparations as arrow poisons to aid in capturing wild game. The name curare is derived from Indigenous words meaning "poison," rendered as ourara, urali, urari, woorali, and woorari.
2 Britannica Sources
1. curare
2. Definition of curare
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How do doctors use curare or similar compounds in modern medicine?
Curare derivatives are used in modern medicine primarily as skeletal muscle relaxants, often administered with general anesthesia for surgeries of the chest and abdomen. Curare functions as a neuromuscular blocking agent, causing muscle relaxation by competing with acetylcholine at the neuromuscular junction, preventing nerve impulses from activating skeletal muscles.

Though effective, curare caused hypotension, limiting its use. It has largely been replaced by curare-like drugs, including atracurium, pancuronium, and vecuronium. Certain curare alkaloids are employed as relaxants to facilitate endotracheal intubation and relieve muscular contractions and convulsions, such as those occurring in tetanus. The effects of curare alkaloids can be reversed by administering an anticholinesterase such as neostigmine, which prevents the destruction of acetylcholine at nerve endings.
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2. drug: Drugs that affect skeletal muscle
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What are the main chemicals found in curare, and how do they work?
Curare is a drug from the alkaloid family, used as a skeletal muscle relaxant during surgery. It contains tubocurarine, the principal alkaloid responsible for its effects.

Curare functions as a neuromuscular blocking agent. It prevents nerve impulses from activating skeletal muscles by competing with the neurotransmitter acetylcholine at the neuromuscular junction, which is the site of chemical communication between a nerve fiber and a muscle cell. This competition results in muscle relaxation, beginning in the toes, ears, and eyes and progressing to the neck, limbs, and finally, the muscles involved in respiration.
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curare, drug belonging to the alkaloid family of organic compounds, derivatives of which are used in modern medicine primarily as skeletal muscle relaxants. Often, curare is administered concomitantly with general anesthesia for certain types of surgeries, particularly those of the chest and the abdomen.

Curare is of botanical origin; its sources include various tropical American plants (primarily Chondrodendron species of the family Menispermaceae and Strychnos species of the family Loganiaceae). Crude preparations of curare have long been used as arrow poisons to aid in the capture of wild game by Indigenous peoples of South America. The name curare is the European interpretation, derived in part from Spanish and Portuguese, of an Indigenous word meaning “poison”; the Indigenous word has been rendered variously as ourara, urali, urari, woorali, and woorari.

Crude curare is a resinous dark brown to black mass with a sticky to hard consistency and an aromatic, tarry odor. Crude preparations of curare were classified according to the containers used for them: pot curare in earthenware jars, tube curare in bamboo, and calabash curare in gourds. Tube curare was the most toxic form, typically being prepared from the woody vine Strychnos toxifera.

In modern medicine, curare is classified as a neuromuscular blocking agent—it produces flaccidity in skeletal muscle by competing with the neurotransmitter acetylcholine at the neuromuscular junction (the site of chemical communication between a nerve fiber and a muscle cell). Acetylcholine normally acts to stimulate muscle contraction; hence, competition at the neuromuscular junction by curare prevents nerve impulses from activating skeletal muscles. The major outcome of that competitive activity is profound relaxation (comparable only to that produced by spinal anesthesia). Relaxation begins in the muscles of the toes, ears, and eyes and progresses to the muscles of the neck and limbs and, finally, to the muscles involved in respiration. In fatal doses, death is caused by respiratory paralysis.

The principal alkaloid responsible for the pharmacological action of curare preparations is tubocurarine, first isolated from tube curare in 1897 and obtained in crystalline form in 1935. Tubocurarine chloride (as d-tubocurarine chloride), isolated from the bark and stems of the South American vine Chondrodendron tomentosum, was the form initially used in medicine. It was first used for general anesthesia in 1942, as the commercial preparation intocostrin. A purer product, tubarine, was made available several years later. Although highly effective as a muscle relaxant, tubocurarine also caused significant hypotension (a drop in blood pressure), which limited its use. It has been largely replaced by various curare-like drugs, including atracurium, pancuronium, and vecuronium.

In addition to inducing skeletal muscle relaxation under general anesthesia, certain curare alkaloids are widely employed as relaxants to facilitate endotracheal intubation (the insertion of a tube into the windpipe to keep the upper airway open in people who are unconscious or unable to breathe on their own). The drugs have also been used to relieve various muscular contractions and convulsions, such as those that occur in tetanus. Patients with neuromuscular disorders such as myasthenia gravis, in which acetylcholine activity is already reduced, are highly sensitive to the effects of curare-like drugs.

Curare alkaloids produce their effects with a minimal concentration of anesthetic agent, which allows patients to recover promptly and reduces the risk of postoperative pneumonias and other complications associated with surgery under general anesthesia. Their effects also can be reversed by the administration of an anticholinesterase such as neostigmine, which prevents the destruction of acetylcholine at nerve endings.

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