Feeling itchy? Blame it on specific nerve cells or neurons, which scientists have now located after many decades of search.
Itchiness was earlier regarded as a less intense version of pain. But researchers now say itch and pain signals are transmitted along different pathways in the spinal cord.
'This finding has very important therapeutic implications,' says Zhou-Feng Chen of the Washington University School of Medicine-St. Louis (WUSM-SL), the study's principal investigator.
'We've shown that particular neurons are critical for the itching sensation but not for pain, which means those cells may contain several itch-specific receptors or signaling molecules that can be explored or identified as targets for future treatment or management of chronic itching,' Chen said.
The new finding follows research by Chen and his team in 2007 that identified the first itch gene, gastrin releasing peptide receptor (GRPR) in the spinal cord, said a WUSM-SL statement.
They also showed that when mice were exposed to things that make them itchy, those without a GRPR gene scratched less than their normal littermates.
These findings appeared in the August issue of Science Express, the advance online publication of Science.