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 Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union

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: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>