Featured Research

from universities, journals, and other organizations

Using morphine after abdominal surgery may prolong pain

Date:
November 12, 2013
Source:
University of Colorado at Boulder
Summary:
Using morphine to fight the pain associated with abdominal surgery may paradoxically prolong a patient's suffering, doubling or even tripling the amount of time it takes to recover from the surgical pain, according to researchers.

Using morphine to fight the pain associated with abdominal surgery may paradoxically prolong a patient's suffering, doubling or even tripling the amount of time it takes to recover from the surgical pain, according to researchers at the University of Colorado Boulder.

The research team from CU-Boulder's Department of Psychology and Neuroscience -- led by Peter Grace, a postdoctoral research fellow, together with Erika Galer, a professional research assistant -- was able to identify the mechanism that caused the prolonged pain. The scientists found that both the morphine and the surgery itself excited glial cells in the nervous system, causing them to send out additional pain signals to the surrounding nerves.

The research findings, which involved a study using rats, are being presented today at the annual meeting of the Society for Neuroscience in San Diego.

"After abdominal surgery -- even without using any drugs to treat the pain -- the glial cells would be activated and they would contribute to the postoperative pain," Grace said. "What we're saying is, if you give them morphine, we also know that contributes to the pain. If you're putting both of those on top of each other, you're going to have a prolonged period of pain."

Past research at CU-Boulder and elsewhere has shown that, while morphine is an effective painkiller, it can also work against itself. Morphine binds to a receptor on neurons to dull the pain, but scientists now know that morphine also binds to a receptor on glial cells in the brain called TLR4, causing them to become excited and intensify the pain.

In the new study, the researchers found that rats that were given morphine for two weeks prior to surgery to treat pre-existing pain -- but that were not given morphine after the procedure -- took six weeks to fully recover from postoperative pain compared with two weeks among rats that were not given the painkiller.

In a second experiment, rats that were treated with morphine for a week after the surgery took four weeks to recover from the postoperative pain compared with two weeks among the control group of rats.

"We're seeing the pain prolong for weeks after the discontinuation of morphine," Grace said.

The research team also tested the effects of the drug (+)-naloxone, which inhibits morphine from binding to the glial cells and exciting them. They found that the use of (+)-naloxone along with the morphine eliminated the extended postoperative pain effect.

The researchers are now studying in more detail how morphine excites glial cells and how (+)-naloxone works to block that process. A better understanding of that pathway in the brain may help researchers find a wider variety of drugs that could be administered along with morphine in the future to limit postoperative pain.


Story Source:

The above story is based on materials provided by University of Colorado at Boulder. Note: Materials may be edited for content and length.


Cite This Page:

University of Colorado at Boulder. "Using morphine after abdominal surgery may prolong pain." ScienceDaily. ScienceDaily, 12 November 2013. <www.sciencedaily.com/releases/2013/11/131112123854.htm>.
University of Colorado at Boulder. (2013, November 12). Using morphine after abdominal surgery may prolong pain. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2013/11/131112123854.htm
University of Colorado at Boulder. "Using morphine after abdominal surgery may prolong pain." ScienceDaily. www.sciencedaily.com/releases/2013/11/131112123854.htm (accessed September 30, 2014).

Share This



More Health & Medicine News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How 'Yes Means Yes' Defines Sexual Assault

How 'Yes Means Yes' Defines Sexual Assault

Newsy (Sep. 29, 2014) Aimed at reducing sexual assaults on college campuses, California has adopted a new law changing the standard of consent for sexual activity. Video provided by Newsy
Powered by NewsLook.com
Scientists May Have Found An Early Sign Of Pancreatic Cancer

Scientists May Have Found An Early Sign Of Pancreatic Cancer

Newsy (Sep. 29, 2014) Researchers looked at 1,500 blood samples and determined people who developed pancreatic cancer had more branched chain amino acids. Video provided by Newsy
Powered by NewsLook.com
Colo. Doctors See Cluster of Enterovirus Cases

Colo. Doctors See Cluster of Enterovirus Cases

AP (Sep. 29, 2014) Doctors at the Children's Hospital of Colorado say they have treated over 4,000 children with serious respiratory illnesses since August. Nine of the patients have shown distinct neurological symptoms, including limb weakness. (Sept. 29) Video provided by AP
Powered by NewsLook.com
Dr.'s Unsure of Cause of Fast-Spreading Virus

Dr.'s Unsure of Cause of Fast-Spreading Virus

AP (Sep. 29, 2014) Doctors at the Children's Hospital of Colorado say they have treated over 4,000 children with serious respiratory illnesses since August. Nine of the patients have shown distinct neurological symptoms, including limb weakness. (Sept. 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins