Physical pain is a near universal problem, whether its sudden pangs or chronic aches. Yet, researchers’ efforts to quash it completely have fallen short—possibly due to a moonlighting channel in nerve cells. But that may be about to change.
The sodium ion channel, called Nav1.7, helps generate the electrical signals that surge through pain-related nerve cells. It’s known to play a key role in pain, but researchers’ past attempts to power-down its charged activities did little to soothe suffering. In a bit of a shocking twist, researchers figured out why; the channel has a second, un-channel-like function—regulating painkilling molecules called opioid peptides. That revelation, published in Nature Communications, provided researchers with the know-how to reverse painlessness in a woman with a rare condition, plus make mice completely pain free.
The link between Nav1.7 and opioid painkillers is “fascinating,” Claire Gaveriaux-Ruff, a pain researcher and professor at the University of Strasbourg, told Ars. And, she added, “this discovery brings hope to the many patients suffering from pain that are not yet adequately treated with the available pain medications.”
That source of hope has been a long time coming, John N. Wood, lead author of the study and a neuroscientist at University College London, told Ars. Researchers have been interested in Nav1.7 for years, he said. Excitement peaked in 2006 when scientists reported finding a family who lacked the channel and could feel no pain at all. After that, researchers excitedly scrambled to relieve pain with Nav1.7-blocking drugs. But the drugs inexplicably failed, Wood said. “So we thought, well maybe this channel isn’t just a channel, maybe it’s got some other activities as well.”