Final answer:
Curare is both a poison and pharmaceutical agent that causes muscle relaxation and paralysis by blocking acetylcholine receptors, which prevents muscle contraction. In medicine, it is utilized during surgical procedures to induce temporary paralysis. Research continues into the medicinal potential of biotoxins, with several drugs already FDA-approved for various conditions.
Step-by-step explanation:
Curare functions as a poison and pharmaceutical by affecting the nervous system. As a poison, typically used by South American indigenous peoples for hunting, curare causes paralysis by blocking the neurotransmitter action of acetylcholine at the neuromuscular junction, leading to muscle relaxation and paralysis. The pharmaceutical application of curare, d-tubocurarine, is to induce temporary muscle paralysis during surgery to prevent involuntary muscle movements and facilitate intubation.
The neurotoxin d-tubocurarine, the active ingredient in curare, binds to the acetylcholine receptors on muscle cells. It competitively blocks these receptors, preventing acetylcholine from attaching and initiating muscle contraction. Unlike nerve poisons such as carbamates and organophosphorus compounds that cause continuous muscle contraction by preventing the breakdown of acetylcholine, curare and compounds like botulinum toxin prevent the release of acetylcholine, resulting in flaccid paralysis.
Medical research has extensively explored the medicinal potential of toxins and venoms from a variety of organisms. The U.S. Food and Drug Administration (FDA) has approved several drugs derived from animal toxins, and research continues to explore new applications for these substances in treating conditions including hypertension, chronic pain, and diabetes. This study of biotoxins is a prime example of applying biological sciences in the field of modern medicine.