Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UT Southwestern researchers find clue to understanding tolerance to drugs of abuse

24.09.2002


Researchers at UT Southwestern Medical Center at Dallas and their colleagues have uncovered new information that will help brain researchers better understand a person’s tolerance to drugs of abuse and open new avenues of investigation into the relationship of addictive-drug usage and the biological causes of mood disorders.



Dr. Michel Barrot, assistant professor of psychiatry at UT Southwestern and lead author of the paper, said researchers used genetically altered mice to show that pain – both physiological and psychological – as well as pleasure can activate changes in the nucleus accumbens, the forebrain structure critical for reward and motivation processes. The findings appeared in a recent issue of Proceedings of the National Academy of Sciences.

Senior author Dr. Eric Nestler, chairman of psychiatry at UT Southwestern, had previously established that drugs of abuse activate CREB, a specific binding protein known for playing a role in the plasticity and adaptation of nerves in the nucleus accumbens. This action between a drug and a binding site is involved with the learning processes and can affect the interaction between subject and environment.


Barrot worked with Nestler on the earlier research that laid the scientific basis for the study in Proceedings.

Researchers reported that they used viral-mediated gene transfer to deliver and overexpress CREB locally, thus mimicking the CREB hyperactivity seen after the delivery of drugs of abuse or exposure to stress. The mice were then tested for their sensitivity to rewards, such as morphine or sucrose, as well as for their sensitivity to anxiety-causing negative situations or painful stimuli.

"In the paper we show that inducing local CREB hyperactivity decreases the emotional response of an animal in different ways, including those that are rewarding, aversive, anxiety-provoking or hurtful," Barrot said. "On the other hand, a decrease in activity in the CREB site causes the opposite reaction. These data suggest the CREB activity in the shell of the nucleus accumbens controls the behavioral responses to emotional stimuli."

Barrot said the manipulation of the behavioral responses to the emotional stimuli "appears to be independent of either positive or negative intensity of the stimulus."

Nestler said, "This work supports the view that brain-reward regions important for addiction may also be involved in symptoms of depression and implicates the critical role of CREB in controlling the activity of these brain regions."

Ann Harrell | EurekAlert!
Further information:
http://irweb.swmed.edu/newspub/newsdetl.asp?story_id=469

More articles from Health and Medicine:

nachricht Inselspital: Fewer CT scans needed after cerebral bleeding
20.03.2019 | Universitätsspital Bern

nachricht Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>