Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Key neural system at risk from fetal alcohol exposure

15.09.2005


In a study of adult monkeys who were exposed to moderate amounts of alcohol in utero, scientists have found that prenatal exposure to alcohol - even in small doses - has pronounced effects on the development and function later in life of the brain’s dopamine system, a critical component of the central nervous system that regulates many regions of the brain.



Writing in the current issue (Sept. 15, 2005) of the journal Alcoholism: Clinical and Experimental Research, a team of researchers led by Mary L. Schneider, a University of Wisconsin-Madison professor of occupational therapy and psychology, reports that when a monkey exposes her fetus to alcohol by drinking, the dopamine system of her offspring is altered. Effects on that key neural system, according to the study’s results, can manifest themselves up to five years after birth, when the monkeys are fully grown.

The influence of alcohol on the dopamine system, depending on the timing of exposure during gestation, varies, says Schneider, but illustrates yet another biological consequence of drinking while pregnant.


"It appears that there is no safe time to drink," says the Wisconsin researcher. "And because our study looked at the effects of lower doses of alcohol than most previous studies, the results suggest there is no safe amount of alcohol that can be consumed during pregnancy. Even moderate drinking can have effects that persist to adulthood."

The new study, conducted at UW-Madison’s Harlow Center for Biological Psychology, looked at the effects of moderate drinking on the offspring of three groups of pregnant rhesus macaques, each of which were provided access to moderate amounts of alcohol during various stages of gestation. In addition, there was a control group not exposed to alcohol.

Working with UW-Madison professor of medical physics Onofre DeJesus, Schneider’s group used PET scans to assess the function of the dopamine system of the adult monkeys exposed to alcohol in utero.

Dopamine is a key chemical messenger in the brain, helping it perform an array of functions ranging from simple movement to cognition to facilitating feelings of enjoyment and motivation. Perhaps the best-known dopamine-related pathology is Parkinson’s disease, caused by the death of the brain cells that normally secrete the chemical. But abnormalities in the functioning of the system can also contribute to such things as addiction, issues of memory, attention and problem solving, and more pronounced conditions such as schizophrenia.

In the new study, Schneider’s group used positron emission tomography or PET on the now-grown monkeys to evaluate the interplay of dopamine receptors and enzymes at work in the system. Schneider and her colleagues were able to see the chemical interplay in the brains of the monkeys exposed to alcohol in utero, and detected a range of effects, especially in the striatum, a region of the brain associated with cognition and other key functions.

"We’re seeing receptors and enzymes that are important in producing dopamine, and what was surprising to us was that dopamine was altered in opposite directions" depending on when during gestation the monkey’s developing brain was exposed to alcohol.

For two groups of monkeys, those exposed during early gestation, when dopamine neurons are first forming in the brain, and those exposed continuously throughout pregnancy, the dopamine system appears to be blunted, Schneider says. "If the dopamine system is blunted, you might not get the usual flushes of dopamine in response toe environmental events, and you may seek alcohol or drugs" as a substitute for the stimulation dopamine normally provides.

For the monkeys exposed to alcohol during middle-to-late gestation, the effect was the opposite: "Animals exposed later had supersensitive (dopamine) receptors. If you have supersensitive receptors, you’re more susceptible to sensory overload and environmental stimuli can become overwhelming."

The new results add to a long list of alcohol’s negative effects on the developing fetus. In the last 30 years, scientists have come to understand that exposing the fetus to alcohol, the drug most widely abused by pregnant women, leads to a host of health and development issues, including low birth weight, facial deformities and mental retardation. The availability of powerful imaging techniques such as PET, which can illustrate the brain at work, are helping scientists make even finer distinctions, linking damage to the developing brain to behavioral problems and learning disabilities later in life.

"This is a big problem," says Schneider. "People have been drinking since Biblical times, but it’s only been within the last few decades that we’ve begun to understand the effects of drinking on fetal health. The term ’fetal alcohol syndrome’ wasn’t even coined until 1973."

Studies of the effects of moderate drinking, says Schneider, are even more recent. The monkeys in her study consumed the equivalent of just one or two drinks a day.

"The blood alcohol content is about .04 or .05. If they were people, they could still drive, but the unseen effects have significant consequences. The take home message from this study is that there is no safe time to drink, even before pregnancy is detected."

Mary Schneider | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Studies and Analyses:

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

Metallic nanoparticles will help to determine the percentage of volatile compounds

20.10.2017 | Materials Sciences

Shallow soils promote savannas in South America

20.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>