Fascinating Facts with Matt

Curare February 25, 2010

Curare, a toxic muscular-skeletal relaxant chemical agent, is found naturally in liana growths in the upper canopy of South American rain-forests. The South American Indians harvested this substance to make a sticky, brown paste that they would poison the tips of their arrows with and these weapons would then be used very effectively in hunting and war. When a victim, say a tapir or a capybara, was hit by a curare-tipped arrow or spear the poison would enter the systemic circulation of the animal and quickly interrupt the synaptic communication of the nervous system bringing on paralysis. With the animal rendered helpless, the hunters would kill, skin and prepare the meat for consumption.

Now you may be beginning to muse to yourself, why does curare cause paralysis in the animals (or even the enemies in war) and not harm the hunters who consume the poisoned meat. Well, it all comes down to the route in which the drug – curare – is administered. When the poisoned arrow tip pierces the hide of an animal, the curare is absorbed immediately into the blood stream where it is sent pumping around the rest of the body. This instant distribution of the drug ensures that it reaches the target (in this case the synaptic cleft) before the drug is metabolised. When the Indians consume the poisoned meat, the drug is entering the body through the oral/gastrointestinal tract route. When any drug is taken orally, the majority of the substance is absorbed in the small intestine and is taken directly to the liver by the portal vein. The liver contains enzymes that breakdown chemical compounds and enable the body to metabolise and eliminate unwanted substances. As such, the curare-tainted meat consumed by the South American Indians did not harm them because the drug was very quickly metabolised by the liver, leaving them with a tasty tapir morsel.