Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scripps Research scientists find key mechanism in transition to alcohol dependence

01.06.2011
Finding could lead to development of drugs that decrease heavy alcohol consumption

A team of Scripps Research Institute scientists has found a key biological mechanism underpinning the transition to alcohol dependence. This finding opens the door to the development of drugs to manage excessive alcohol consumption.

"Our focus in this study, like much of our lab's research, was to examine the role of the brain's stress system in compulsive alcohol drinking driven by the aversive aspects of alcohol withdrawal," said Scripps Research Associate Professor Marisa Roberto, Ph.D., senior author of the study.

"A major goal for this study," added Research Associate Nicholas Gilpin, Ph.D., the paper's first author, "was to determine the neural circuitry that mediates the transition to alcohol dependence."

In the new research, published in the June 1, 2011 issue of the journal Biological Psychiatry, the Scripps Research scientists demonstrated the key role of a receptor —a structure that binds substances, triggering certain biological effects—for neuropeptide Y in a part of the brain known as the central amygdala. The amygdala, a group of nuclei deep within the medial temporal lobes, performs an important role in the processing and memory of emotional reactions.

"We've known for quite some time that neuropeptide Y is an endogenous [naturally occurring] anti-stress agent," says Markus Heilig, clinical director of the National Institute of Alcohol Abuse and Alcoholism (NIAAA). "We've also known that development of alcohol dependence gives rise to increased sensitivity to stress. This paper elegantly and logically brings these two lines of research together. It supports the idea that strengthening neuropeptide Y transmission in the amygdala would be an attractive treatment for alcoholism. The challenge remains to develop clinically useful medications based on this principle."

Discovering the Circuitry

Building on Gilpin's previous work on neuropeptide Y, in the new project, Gilpin, Roberto, and colleagues observed the effects of the administration neuropeptide Y in the central amygdala on alcohol drinking in rats. Alcohol-dependent rats were allowed to press levers for ethanol and water during daily withdrawal from chronic alcohol exposure.

"Normally, the transition to alcohol dependence is accompanied by gradually escalating levels of alcohol consumption during daily withdrawals," Gilpin explained. "The aim of this protocol was to examine whether neuropeptide Y infusions during daily withdrawals would block this escalation of alcohol drinking."

The scientists report a suppression of alcohol consumption with chronic neuropeptide Y infusions and detailed some of the neurocircuitry involved. Ethanol normally produces robust increases in inhibitory GABAergic transmission—GABA is another neurotransmitter—in the central amygdala, but this effect is blocked and reversed by neuropeptide Y.

Gilpin notes the scientists were surprised at one aspect of the findings—the role of a subset of neuropeptide Y receptors known as Y2 receptors. "Previous behavioral evidence suggested that antagonism of Y2 receptors in whole brain suppresses alcohol drinking, similar to the effects of neuropeptide Y," he said. "However, our data suggest that Y2 receptor blockade in central amygdala might actually increase alcohol drinking, presumably by affecting pre-synaptic release of GABA. These data also suggest that antagonism of post-synaptic Y1 receptors in central amygdala provides a viable pharmacotherapeutic strategy, a hypothesis supported by previous work from other labs."

Two additional aspects of the findings are worth noting, Roberto says. First, repeated neuropeptide Y administration not only blocked the development of excessive alcohol consumption in dependent rats, but also tempered the moderate increase in alcohol consumption following periods of abstinence in non-dependent rats. Second, neuropeptide Y exhibited long-term efficacy in suppressing alcohol self-administration, highlighting the potential of neuropeptide Y treatments for a clinical setting.

In addition to Roberto and Gilpin, authors of this paper, titled "Neuropeptide Y Opposes Alcohol Effects on GABA Release in Amygdala and Blocks the Transition to Alcohol Dependence" and scheduled to appear in the June 1, 2011 print edition of Biological Psychiatry, include Kaushik Misra, Melissa Herman, Maureen Cruz, and George Koob, all of Scripps Research. See http://www.ncbi.nlm.nih.gov/pubmed/21459365 .

This project was supported by the National Institutes of Health's National Institute on Alcohol Abuse and Alcoholism, and the Pearson Center for Alcoholism and Addiction Research at Scripps Research.

About The Scripps Research Institute

The Scripps Research Institute is one of the world's largest independent, non-profit biomedical research organizations. Scripps Research is internationally recognized for its discoveries in immunology, molecular and cellular biology, chemistry, neuroscience, and vaccine development, as well as for its insights into autoimmune, cardiovascular, and infectious disease. Headquartered in La Jolla, California, the institute also includes a campus in Jupiter, Florida, where scientists focus on drug discovery and technology development in addition to basic biomedical science. Scripps Research currently employs about 3,000 scientists, staff, postdoctoral fellows, and graduate students on its two campuses. The institute's graduate program, which awards Ph.D. degrees in biology and chemistry, is ranked among the top ten such programs in the nation. For more information, see www.scripps.edu.

Mika Ono | EurekAlert!
Further information:
http://www.scripps.edu

More articles from Health and Medicine:

nachricht Collagen nanofibrils in mammalian tissues get stronger with exercise
14.12.2018 | University of Illinois College of Engineering

nachricht New discoveries predict ability to forecast dementia from single molecule
12.12.2018 | UT Southwestern Medical Center

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: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>