London, June 6: A new study, led by an Indian-origin scientist at the Indiana University School of Medicine, has reported the discovery of a peptide that short circuits a pathway for chronic pain.

Unlike current treatments, this peptide does not exhibit deleterious side effects such as reduced motor coordination, memory loss, or depression.

The peptide, CBD3, has been shown in mice to interfere with signals that navigate calcium channels to produce pain.

Unlike other substances that block pain signals, CBD3 does not directly inhibit the influx of calcium. This is important as influx of calcium regulates heart rhythm and vital functions in other organs.

Rajesh Khanna, Ph. D., assistant professor of pharmacology and toxicology at the Indiana University School of Medicine, said the peptide discovered by him and his colleagues is potentially safer to use than addictive opioids or cone snail toxin Prialt-a recognized analgesic that is injected into the spinal column, both of which can cause respiratory distress, cardiac irregularities and other problems.

"After opioids-the gold standard for pain control -- the next target is calcium channels," said Dr. Khanna.

"Along the pain pathway in the spinal cord, there are pain-sensing neurons called nociceptors that have an abundance of calcium channels."

CBD3 can be given systemically and blocks pain in a variety of acute as well as chronic pain models, said Khanna.

The novel peptide binds to the calcium channel and reduces the number of excitability signals without disrupting the beneficial global calcium flow. Upon reaching the brain, these signals are interpreted as the sensation of pain.

The study is published in Nature Medicine. (ANI)