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:2/12/2016)... Malvern, Pa. (PRWEB) , ... February 12, 2016 ... ... help sort through a world of exterior design possibilities. CertainTeed, North America’s leading ... visualization tools by expanding the product offerings showcased in the mobile version of ...
(Date:2/12/2016)... ... February 12, 2016 , ... Healthcare careers in the medical laboratory, ... jobs via the website of healthcare staffing leader Aureus Medical Group during the month ... , travel therapy positions and in travel and direct hire opportunities in ...
(Date:2/12/2016)... ... 2016 , ... Yisrayl Hawkins, Pastor and Overseer at The House of Yahweh ... says are the real facts surrounding all those Bible stories. For generations families have ... teachers, and Yisrayl says there is more to these than just mere “stories”. ...
(Date:2/12/2016)... ... February 12, 2016 , ... With the exception of restorative dentistry, to date there ... With the recent approval by the FDA, there is a now a new protocol ... varnish, SDF is very simple and quick to apply. The application is as simple ...
(Date:2/11/2016)... ... ... “ HEALING MIND : Five Steps to Ultimate Healing, Four Rooms for ... readers how to become their own therapist. Providing a useful step-by-step process for achieving ... an understanding of how to heal one’s inner child using four archetypes of Christianity. ...
Breaking Medicine News(10 mins):
(Date:2/11/2016)... , Feb. 11, 2016  Walgreens has committed to ... states and Washington, D.C. as part ... that was commended by shareholder advocacy organization As You Sow. ... You Sow. "Many people hold on to unneeded drugs because ... have tragic consequences." --> Conrad MacKerron , ...
(Date:2/11/2016)... 11, 2016   Health 2.0 , the premiere ... technologies, announced today " 10 Year Global Retrospective ", ... over the past ten years.   ... Health 2.0 has served as the preeminent thought-leader in ... thousands of technologies, companies, innovators, and patient-activists through an ...
(Date:2/11/2016)...  NOIT™ Research LLC, a private, leading-edge autism research ... to assist needy families in obtaining one of its ... February 10, 2016 and March 31, 2016, the company ... NOIT is an auditory stimulus that plays a key ... Beth Shier , NOIT Research director. ...
Breaking Medicine Technology: