Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify molecule that helps the sleep-deprived to mentally rebound

26.02.2009
Sleep experts know that the mental clarity lost because of a few sleepless nights can often be restored with a good night’s rest. Now, UT Southwestern Medical Center researchers have identified a key molecular mechanism that regulates the brain’s ability to mentally compensate for sleep deprivation.

Working with mice, they found that a molecule called an adenosine receptor is necessary for sleep-restricted animals to attain adequate levels of slow-wave activity in the brain once normal sleep resumes. It is this increase in slow-wave activity, or SWA, during rebound sleep that helps restore normal working memory and attention skills to the sleep-deprived, the scientists report in the Feb. 4 issue of the Journal of Neuroscience.

“Normal society pushes people to burn candles at both ends — going to bed late, getting up early, and somehow performing mentally with lack of adequate sleep,” said senior author Dr. Robert Greene, professor of psychiatry at UT Southwestern. “We need to have our adenosine receptors intact to do that.”

Adenosine receptors on nerve cells, including brain cells, are akin to docking points for the molecule adenosine. Adenosine levels increase in the brain with each hour of waking activity, and “docking” of the molecule with its receptor is shown in this study to help promote the slow-wave activity of sleep. Scientists have known that recovery from sleep deprivation involves not only an increase in sleep time, or rebound sleep, but also an elevation in this slow-wave activity.

To investigate how adenosine receptors and SWA might be linked, Dr. Greene and his team engineered mice that lacked a receptor to pair up with adenosine.

Sleep-restricted mice were kept awake by being placed on a moving treadmill. Researchers then electronically monitored sleep and waking activity of both normal and genetically engineered mice, including monitoring electronically the brain waves of the animals. The mice also traveled a maze with eight paths, each with a piece of chocolate at the end of it.

Electronic measurements showed that, unlike normal mice, the mice lacking the adenosine receptor could not increase the intensity of their slow-wave activity in response to the sleep deprivation. Under normal sleep conditions both the normal and mutant mice were almost error-free on the maze test. However, when sleep-deprived, the engineered mice made significantly more errors on the maze test than their normal counterparts. This type of skills test represents the human equivalent of the attention and working memory needed to multitask or build on tasks already done, such as being given a phone number, reaching for a pen to write it down and recalling the number, said Dr. Greene.

Linking the lack of functioning adenosine receptors to depressed normal SWA rebound response might aid in developing treatments for people with sleep-related cognitive deficits, he said.

The research also further explains the effects of caffeine, which also “docks” to adenosine receptors, preventing the docking of adenosine and keeping the caffeine-drinker awake. Dr. Greene compared the study mice’s behavior response on the maze test to how a person drinking a “permanent cup of coffee” might behave.

“They probably won’t get the regular amount of slow-wave activity or deep sleep as they normally would,” Dr. Greene said. “This is not to say that coffee is bad, but drinking it all the time or in the evening could affect your mental performance the next day.”

The researchers next will investigate the relationship between sleep, adenosine and energy metabolism, a biological process in which adenosine plays a key role.

Other researchers from UT Southwestern involved in the study were lead author Dr. Theresa Bjorness, postdoctoral research fellow in psychiatry, and Virginia Poffenberger, research technician in psychiatry.

The study was funded by the U.S. Department of Veterans Affairs and the National Institutes of Health.

LaKisha Ladson | EurekAlert!
Further information:
http://www.utsouthwestern.org/neurosciences
http://www.utsouthwestern.edu

More articles from Life Sciences:

nachricht Immune Defense Without Collateral Damage
23.01.2017 | Universität Basel

nachricht The interactome of infected neural cells reveals new therapeutic targets for Zika
23.01.2017 | D'Or Institute for Research and Education

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Tracking movement of immune cells identifies key first steps in inflammatory arthritis

23.01.2017 | Health and Medicine

Electrocatalysis can advance green transition

23.01.2017 | Physics and Astronomy

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>