Featured Research

from universities, journals, and other organizations

Missing enzyme linked to drug addiction

Date:
June 17, 2013
Source:
Endocrine Society
Summary:
A missing brain enzyme increases concentrations of a protein related to pain-killer addiction, according to an animal study.

A missing brain enzyme increases concentrations of a protein related to pain-killer addiction, according to an animal study.

The results will be presented Monday at The Endocrine Society's 95th Annual Meeting in San Francisco.

Opioids are pain-killing drugs, derived from the opium plant, which block signals of pain between nerves in the body. They are manufactured in prescription medications like morphine and codeine, and also are found in some illegal drugs, like heroin. Both legal and illegal opioids can be highly addictive.

In addition to the synthetic opioids, natural opioids are produced by the body. Most people have heard of the so-called feel-good endorphins, which are opioid-like proteins produced by various organs in the body in response to certain activities, like exercise.

Drug addiction occurs, in part, because opioid-containing drugs alter the brain's biochemical balance of naturally produced opioids. Nationwide, drug abuse of opioid-containing prescription drugs is skyrocketing, and researchers are trying to identify the risk factors that differentiate people who get addicted from those who do not.

In this particular animal model, researchers eliminated an enzyme called prohormone convertase 2, or PC2, which normally converts pre-hormonal substances into active hormones in certain parts of the brain. Previous research by this team demonstrated that PC2 levels increase after long-term morphine treatment, according to study lead author Theodore C. Friedman, MD, PhD, chairman of the internal medicine department at Charles R. Drew University of Medicine and Science in Los Angeles.

"This raises the possibility that PC2-derived peptides may be involved in some of the addiction parameters related to morphine," Friedman said.

For this study, Friedman and his co-researchers analyzed the effects of morphine on the brain after knocking out the PC2 enzyme in mice. Morphine normally binds to a protein on cells known as the mu opioid receptor, or MOR. They found that MOR concentrations were higher in mice lacking PC2, compared to other mice.

To analyze the effects of PC2 elimination, the researchers examined MOR levels in specific parts of the brain that are related to pain relief, as well as to behaviors associated with reward and addiction. They measured these levels using a scientific test called immunohistochemistry, which uses specific antibodies to identify the cells in which proteins are expressed.

"In this study, we found that PC2 knockout mice have higher levels of MOR in brain regions related to drug addiction," Friedman said. "We conclude that PC2 regulates endogenous opioids involved in the addiction response and in its absence, up-regulation of MOR expression occurs in key brain areas related to drug addiction."

The National Institutes of Health's National Institute on Drug Abuse funded the study.


Story Source:

The above story is based on materials provided by Endocrine Society. Note: Materials may be edited for content and length.


Cite This Page:

Endocrine Society. "Missing enzyme linked to drug addiction." ScienceDaily. ScienceDaily, 17 June 2013. <www.sciencedaily.com/releases/2013/06/130617172831.htm>.
Endocrine Society. (2013, June 17). Missing enzyme linked to drug addiction. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2013/06/130617172831.htm
Endocrine Society. "Missing enzyme linked to drug addiction." ScienceDaily. www.sciencedaily.com/releases/2013/06/130617172831.htm (accessed July 24, 2014).

Share This




More Mind & Brain News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
China's Ageing Millions Look Forward to Bleak Future

China's Ageing Millions Look Forward to Bleak Future

AFP (July 24, 2014) China's elderly population is expanding so quickly that children struggle to look after them, pushing them to do something unexpected in Chinese society- move their parents into a nursing home. Duration: 02:07 Video provided by AFP
Powered by NewsLook.com
Idaho Boy Helps Brother With Disabilities Complete Triathlon

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Newsy (July 23, 2014) An 8-year-old boy helped his younger brother, who has a rare genetic condition that's confined him to a wheelchair, finish a triathlon. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
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:
from the past week

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