Scientists have discovered nerve cells that deal solely with itching sensations in a major breakthrough for pain relief.
The breakthrough could lead to a new generation of anti-itch treatments targetting the new cells.
Many experts had previously thought that the receptors for pain and itching were linked.
However, the team from Johns
Hopkins University found that certain nerve cells, calle dMrgprA3+, are
specialized to detect itchy sensations - and those receptors don’t
detect painful sensations.
'Itch-specific neurons have been sought for decades, the researchers say in their paper, published in Nature Neuroscience.
'The existence of such neurons has been doubted recently as a result of the observation that itch-mediating neurons also respond to painful stimuli.
To identify cells that sense itching, Xinzhong Dong, a neuroscientist at Johns Hopkins University, genetically engineered mice whose nerve cells glowed fluorescent green when they fired.
The researchers then exposed the mice to a series of irritating compounds, such as histamine and the active ingredient in itching powder, and looked for nerves that glowed green.
The researchers then burnt out the nerves that lit up, and found the mice scratched a lot less.
Researchers now hope they can silence those cells to develop better anti itch treatments.
'Our study opens new avenues for studying itch
and developing anti-pruritic therapies,' they say.
The newly discovered itch nerves sit inside the spine, near the spinal cord, and only innervate locations within the skin.
That explains why people feel the urge to scratch their skin, but don’t feel itchy in internal organs, Dong told LiveScience.
'You can't have an itchy pancreas,' he said.
The breakthrough could lead to a new generation of anti-itch treatments targetting the new cells.
Many experts had previously thought that the receptors for pain and itching were linked.
The cause of the itch? Scientists were able to identify the 'itch' cells, shown here lit up in mice
'Itch-specific neurons have been sought for decades, the researchers say in their paper, published in Nature Neuroscience.
'The existence of such neurons has been doubted recently as a result of the observation that itch-mediating neurons also respond to painful stimuli.
To identify cells that sense itching, Xinzhong Dong, a neuroscientist at Johns Hopkins University, genetically engineered mice whose nerve cells glowed fluorescent green when they fired.
The researchers then exposed the mice to a series of irritating compounds, such as histamine and the active ingredient in itching powder, and looked for nerves that glowed green.
The researchers then burnt out the nerves that lit up, and found the mice scratched a lot less.
Researchers now hope they can silence those cells to develop better anti itch treatments.
The discovery could be a major breakthrough for sufferers of severe itching. Researchers hope it could lead to new treatments
The newly discovered itch nerves sit inside the spine, near the spinal cord, and only innervate locations within the skin.
That explains why people feel the urge to scratch their skin, but don’t feel itchy in internal organs, Dong told LiveScience.
'You can't have an itchy pancreas,' he said.
To identify cells that sense itching, Xinzhong
Dong, a neuroscientist at Johns Hopkins University, genetically
engineered mice whose nerve cells glowed fluorescent green when they
fired, above.