When they do, and when the right balance of openings and closings occurs all over a nerve ending, that nerve will fire, ultimately passing a signal along the nerve fibers that connect the brain with our eyes, noses, fingers, tongues and other surfaces on our bodies.
Those various signals say to the brain "hot," "cold," "hard," "soft" or "bitter" cues that give life to our perception of the world around us. This basic physiology both enables us to experience all the soft, warm, pleasant things in life but also warns our brains about dangers.
Pain is one of the most important alerts for our brain that we are at risk of injury, causing us to wince, squint, gasp or otherwise pull away to protect ourselves.
At the same time, pain often outlives its usefulness as a warning system. In many people with disease or injuries, the pain can become chronic and debilitating. Moreover, not all pain is accurately perceived by the brain. Numerous plants, insects, reptiles and other creatures have evolved the ability to produce toxins or venoms for hunting or to protect themselves against predation. These venoms co-opt the human sensory systems and can trigger severe pain.
The venom of the Texas coral snake may be an example of this, said Julius.
"Presumably these toxins have evolved as anti-predatory mechanisms to protect the animal," he said. The work follows up on earlier discoveries Julius and his colleagues have made involving the spice of chili peppers, wasabi and mint, and how their chemicals work in the body.
How the Venom Works
In the study, Julius' graduate student Christopher J. Bohlen screened venom taken from numerous snakes and provided by collaborator Elda E. Sánchez of the National Natural Tox
|Contact: Jason Socrates Bardi|
University of California - San Francisco