Navigation Links
Itching Not a Less Intense Form of Pain
Date:11/18/2008

Each are regulated by different molecular mechanisms, scientists show

TUESDAY, Nov. 18 (HealthDay News) -- Pain and itching are regulated by different molecular mechanisms, according to a Washington University study that challenges the long-held belief that itching is a less intense version of the body's response to pain.

This finding could prove important in improving treatment of chronic itching and pain.

Zhou-Feng Chen, of Washington University's Pain Center, in St. Louis, and colleagues found that pain signals are not affected in mice bred without an itch gene called gastrin-releasing peptide receptor (GRPR) or when the gene's actions are blocked. When the mice without the GRPR gene were exposed to itchy stimuli, they scratched less than normal mice.

GRPR, previously identified by the same team of researchers, makes a receptor found in a small number of nerve cells in a region of the spinal cord that transmits itch and pain signals, as well as temperature sensation, from the skin to the brain.

"There are two major types of itching," explained Chen, an associate professor of anesthesiology, psychiatry and developmental biology. Histamine-dependent itching is caused by bug bites or allergic reactions and can be treated with antihistamine drugs. Chronic, severe itching often occurs as a side effect of spinal injections of opioid drugs, such as morphine, given to chronic pain patients. This type of itching can't be relieved by antihistamines.

"Most scientists believed that the itching could not be separated from the drug's pain-killing effects," Chen said. But he and his team thought GRPR may be responsible for the itching but involved in the pain response.

"If we inject a GRPR inhibitor and morphine into the mouse spinal cord, the drug still has its normal analgesic effect, but the mice don't scratch. This is very interesting, because it demonstrates that analgesia and itching can be separated. There may be itch-specific genetic pathways in the spinal cord that are not related to pain sensation," Chen said.

Like mice, humans also have GRPR genes, so it may be possible to treat chronic itching in humans using a similar approach.

"Our findings could have important therapeutic implications. More research needs to be done, but it may be possible to relieve itching in patients by blocking GRPR function without affecting the pain pathway," Chen said.

The study was presented Monday at the Society for Neuroscience annual meeting, in Washington, D.C.

More information

The American Academy of Dermatology has more about itching.



-- Robert Preidt



SOURCE: Washington University School of Medicine in St. Louis, news release, Nov. 17, 2008


'/>"/>
Copyright©2008 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Walgreens Pays $35 Million, Settles Pharmacist-Whistleblower Qui Tam Drug Switching Allegations
2. Attorney General Corbett Announces $36.7 Million Multi-State Settlement With CVS/Caremark in National Dosage-Switching Investigation
3. CVS, Americas Largest Pharmacy Chain, Pays Nearly $37 Million to Settle Federal and State Generic Drug Switching Charges
4. Playing Catch in Winter Could Save Kids Pitching Arms
5. How pitching changes little leaguers shoulders
6. Switching to MA Coverage Unlikely for Current Beneficiaries With MediGap or Medicare Only
7. Ultra-fast, ultra-intense laser has clean-cut advantage
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Itching Not a Less Intense Form of Pain
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Comfort Keepers® ... American Cancer Society and the Road To Recovery® program to drive cancer patients to ... and other adults to ensure the highest quality of life and ongoing independence. ...
(Date:6/24/2016)... ... , ... People across the U.S. are sharpening their pencils and honing their ... in which patients and their families pay tribute to a genetic counselor by nominating ... of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. , In April, ...
(Date:6/24/2016)... York, NY (PRWEB) , ... June 24, 2016 ... ... publication Haute Living, is proud to recognize Dr. Barry M. Weintraub as a ... that “the most beautiful women in the world, and the most handsome men, ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... feeding the Frederick area economy by obtaining investment capital for emerging technology companies. ... 2½ years that have already resulted in more than a million dollars of ...
(Date:6/24/2016)... ... June 24, 2016 , ... Venture Construction Group ... Tournament held on June 20th at the Woodmont Country Club at 1201 Rockville ... an organization dedicated to helping service members that have been wounded in battle and ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... -- Research and Markets has announced ... Applications, Technologies, Forecasts" report to their offering. ... Smart Skin, Structural Health Monitoring, Composite Smart Structures, ... involves electronic and/or electrical components and circuits that ... such as vehicle bodies or conformally placed upon ...
(Date:6/24/2016)... 2016 Research and Markets has announced ... Diagnostic Tests" report to their offering. ... The World Market for Companion Diagnostics covers ... Market analysis in the report includes the following: ... Diagnostic Kits) by Region (N. America, EU, ROW), 2015-2020 ...
(Date:6/24/2016)... June 24, 2016  Arkis BioSciences, a leading ... and more durable cerebrospinal fluid treatments, today announced ... Series-A funding is led by Innova Memphis, followed ... other private investors.  Arkis, new financing will accelerate ... the market release of its in-licensed Endexo® technology. ...
Breaking Medicine Technology: