Featured Research

from universities, journals, and other organizations

Rutgers Scientists Pinpoint Brain Cells Involved In Drug Addiction Relapse

Date:
August 20, 2003
Source:
Rutgers, The State University Of New Jersey
Summary:
Relapse among recovering drug addicts can now be linked to specific nerve cells in a particular region of the brain, according to a team of researchers at Rutgers, The State University of New Jersey. The discovery may help pave the way for new addiction therapies and intervention strategies.

NEW BRUNSWICK/PISCATAWAY, N.J. – Relapse among recovering drug addicts can now be linked to specific nerve cells in a particular region of the brain, according to a team of researchers at Rutgers, The State University of New Jersey. The discovery may help pave the way for new addiction therapies and intervention strategies.

Long after an addict has become drug-free, simple events or circumstances that were associated with prior drug use, such as walking through a particular neighborhood or hearing a particular song, can reawaken memories that trigger a craving and provoke a relapse. These environmental stimuli may render an addict vulnerable to a return to compulsive drug use.

"We've identified a part of the brain that appears to process these memories," said Rutgers psychology professor Mark West. "This might be one of the brain areas that a very skilled pharmacological approach could target."

West and his Rutgers colleagues published their findings in the Aug. 13 issue of the Journal of Neuroscience. They concentrated their work on nerve cells or neurons in the nucleus accumbens, a brain region known to be involved in the addictive effects of drugs.

They were searching for those nerve cells that respond to a drug-associated environmental stimulus. The laboratory work employed a design, previously demonstrated to be a good model of human addiction, in which rats were able to self-administer a specific drug. The animals were provided cocaine, one of the most highly addictive narcotics, dispensed to them when they pressed a lever. Microelectrodes that recorded the activity of single neurons were used to monitor nerve cells in a part of the nucleus accumbens known as the shell.

As the animals self-administered the cocaine, a tone was sounded and they came to associate the tone with the drug. If an animal pressed the lever in the absence of the tone, no cocaine was dispensed. At the end of three weeks, the rats had learned to press the lever when they heard the tone. Next, both the drug and the lever were removed. After a month, the lever – but no cocaine – was returned to the cage but was virtually ignored by the animals – until the tone was again sounded.

"When we started to play the tone that had been paired with cocaine, the animals began to press the lever at a fairly high rate," said West. "It indicated that the animals had a persistent memory – they remembered the significance of the tone. We interpreted the resumption of lever pressing as a behavioral relapse." During this relapse of drug seeking, brain activity recordings showed that accumbens shell neurons responded almost instantaneously when the tone was sounded. In contrast, accumbens neurons had not responded to the tone before conditioning.

Eventually the animals gave up pressing the lever, even in the presence of the tone, since no cocaine was forthcoming. "Even though the lever pressing behavior was extinguished, we were still seeing accumbens neuron activity in response to the tone," said West.

West explained that the brain is slow to forget the stimuli. After a relatively long period of drug abstinence, the persistence of the memories – those conditioned associations reflected in the neural activity – may partially explain why treating drug addiction is an uphill battle, West observed.

"The neural mechanisms of learning are still not understood. This is what we were investigating here – neural mechanisms in one part of a brain circuit that participate in creating memories of these environmental stimuli," said West. "As medical science seeks to develop chemicals that alleviate drug craving, our data may help scientists or clinicians know what part of the brain to target. With cocaine, we haven't yet discovered a magic bullet that can go in and just cure the problem."


Story Source:

The above story is based on materials provided by Rutgers, The State University Of New Jersey. Note: Materials may be edited for content and length.


Cite This Page:

Rutgers, The State University Of New Jersey. "Rutgers Scientists Pinpoint Brain Cells Involved In Drug Addiction Relapse." ScienceDaily. ScienceDaily, 20 August 2003. <www.sciencedaily.com/releases/2003/08/030820073750.htm>.
Rutgers, The State University Of New Jersey. (2003, August 20). Rutgers Scientists Pinpoint Brain Cells Involved In Drug Addiction Relapse. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2003/08/030820073750.htm
Rutgers, The State University Of New Jersey. "Rutgers Scientists Pinpoint Brain Cells Involved In Drug Addiction Relapse." ScienceDaily. www.sciencedaily.com/releases/2003/08/030820073750.htm (accessed July 25, 2014).

Share This




More Mind & Brain News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
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
Can Watching TV Make You Feel Like A Failure?

Can Watching TV Make You Feel Like A Failure?

Newsy (July 24, 2014) A study by German researchers claims watching TV while you're stressed out can make you feel guilty and like a failure. 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

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