Curare

Curare is a poison found in the Strychnos toxifera plant used by the South American indigenous tribes.

The main toxin is D-tubocurarine

It is a muscle relaxant which binds to the Nicotinic acetylcholine receptors. Curare is a competative antagonist, in which it binds to the sites for the receptor with a higher affinity than that of acetylcholine.

Curare has been used for its anaestheic properties for many years. Previously the cyclopropane anaesthesia caused severe cardiovascular depression, due to the depth of the anaesthesia caused. (Foldes FF. 2003)