Philosophy
A human phenomenon that irritates and provides pleasure. Itches...from allergies, noxious plants, pesky insects, disease, infections, wound healing...and it does feel good to scratch. Scratching does come with a risk--more infection. Why would pleasure be associated with a miserable itch? Nevertheless, scientists have made some progress in finding the "itchy" source.
WASHINGTON--Researchers have found specific nerve cells responsible for itchiness, a discovery that could lead to better treatments for skin conditions.
Experiments on mice show they have nerve cells that convey only an itch sensation -- contradicting common wisdom that itch and pain are closely related.
Reporting in the journal Science, researchers at Washington University School of Medicine in St. Louis and Peking University Third Hospital in Beijing said they created itch-free mice by killing their itch-specific neurons.
"This finding has very important therapeutic implications," Washington University's Zhou-Feng Chen, who led the study, said in a statement.
"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."
Eczema, psoriasis, allergies, infections and other conditions can cause chronic itching and various treatments are often only partially effective.
In 2007 the researchers identified the first itch gene called gastrin-releasing peptide receptor, or GRPR. It was active in the spinal cord.
"But the identification of an itch receptor in spinal-cord neurons didn't mean those neurons were itch-specific because it was possible that they also could have pain-related genes," Chen said.
So they destroyed nerve cells that had active GRPR, using a toxin that attaches to GRPR and injecting it into the spinal cords of mice.
When the mice then were exposed to things that caused itching, they did not scratch. But they felt pain.
"This is a very striking and unexpected result because it suggests there is an itch-specific neuronal pathway in the spinal cord," Chen said.
"We've shown that these GRPR neurons are important for itching sensation and not for pain, but we really don't know much more about them," Chen said. "We still have a lot of questions, and we are very interested to find more answers."
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Philosophy
Itchy and scratchy--pain and pleasure
A human phenomenon that irritates and provides pleasure. Itches...from allergies, noxious plants, pesky insects, disease, infections, wound healing...and it does feel good to scratch. Scratching does come with a risk--more infection. Why would pleasure be associated with a miserable itch? Nevertheless, scientists have made some progress in finding the "itchy" source.
"Scientists find nerve cells responsible for itch"
August 6th, 2009
Reuters
August 6th, 2009
Reuters
WASHINGTON--Researchers have found specific nerve cells responsible for itchiness, a discovery that could lead to better treatments for skin conditions.
Experiments on mice show they have nerve cells that convey only an itch sensation -- contradicting common wisdom that itch and pain are closely related.
Reporting in the journal Science, researchers at Washington University School of Medicine in St. Louis and Peking University Third Hospital in Beijing said they created itch-free mice by killing their itch-specific neurons.
"This finding has very important therapeutic implications," Washington University's Zhou-Feng Chen, who led the study, said in a statement.
"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."
Eczema, psoriasis, allergies, infections and other conditions can cause chronic itching and various treatments are often only partially effective.
In 2007 the researchers identified the first itch gene called gastrin-releasing peptide receptor, or GRPR. It was active in the spinal cord.
"But the identification of an itch receptor in spinal-cord neurons didn't mean those neurons were itch-specific because it was possible that they also could have pain-related genes," Chen said.
So they destroyed nerve cells that had active GRPR, using a toxin that attaches to GRPR and injecting it into the spinal cords of mice.
When the mice then were exposed to things that caused itching, they did not scratch. But they felt pain.
"This is a very striking and unexpected result because it suggests there is an itch-specific neuronal pathway in the spinal cord," Chen said.
"We've shown that these GRPR neurons are important for itching sensation and not for pain, but we really don't know much more about them," Chen said. "We still have a lot of questions, and we are very interested to find more answers."
- Is Pain Like Water?
Water is what philosophers call a natural kind, that is it is a thing found in nature that has a grouping definable in terms of purely natural properties. Water isn't just related to having the chemical make-up of H2O, to be water IS to have the chemical...
- Jeremy Bentham In The Lab
I've got a colleague who does pain research (and, no, there is no truth to the rumor that my 8 am logic class is one of his experiments). He studies physiological issues related to pain. Where pain is usually the result of an undesirable change to...
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"The Day When Neurons Go on Trial" by Jim Dwyer September 17th, 2013 The New York Times Here are law students on a Tuesday morning in 2013, hearing that researchers hope over the next decade or so to map the wiring of the human brain, seeing how individual...
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If you have it, spend it. "Marilyn Monroe's Seven Year Itch dress sells for $4.6m" June 19th, 2011 BBC NEWS The white dress worn by Marilyn Monroe in the 1955 film The Seven Year Itch has sold for $4.6m (£2.8m) at an auction in Los Angeles. The...
- Kavli Prize 2008 Winners
Remember this... Science accolades...more Nobel-like awards? The 2008 winners... "7 scientists share $1 million prizes for research" by Malcolm Ritter May 28th, 2008 U.S.News & World Report New York: Three prizes worth $1 million apiece were awarded...