Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sleep and sedation controlled in same brain centre, say scientists

26.08.2002


Undergoing anaesthesia may be more like falling asleep than we once thought, according to new research from Imperial College London and Harvard Medical School, USA.



Researchers report today in the journal Nature Neuroscience how two of the most widely used anaesthetics, pentobarbital and propofol induce sleep by mimicking the natural process of falling into a deep sleep.

Using behavioural studies and molecular imaging techniques in rats, the team of basic scientists and clinicians found that the sleep-inducing action of anaesthetics is localised to a small area of the brain, the tuberomammillary nucleus (TMN), part of the hypothalamic region that controls other fundamental processes such as breathing and temperature regulation.


The team showed that the anaesthetics produce their sedative effect by locking on to a specific type of neurotransmitter receptor in the TMN called GABA-A.

GABA-A receptors have an inhibitory action, hence when anaesthetic molecules bind to them they stop the nerve cells from sending electrical signals to other neurons.

"The sleep-inducing action of general anaesthetics occurs by hijacking one pathway in the brain responsible for promoting deep sleep," said Professor Nick Franks of Imperial College London.

"The TMN region of the brain is part of a key switching mechanism in the sleep/wake cycle. When stimulated, it sends excitatory signals to other parts of the brain telling the body to be awake. TMN neurons are pharmacologically inhibited by the negative action of the anaesthetics binding to the GABA-A receptor - leading to a sleep induced state," said Professor Franks.

"Although not all anaesthetics exert their sedative effect using GABA-A receptors, the research is significant because it indicates that the sleep-inducing effect of anaesthetics acts on specific areas of the brain," he added.

Professor Mervyn Maze, Head of the Department of Anaesthetics and Intensive Care at Imperial College London and senior author of the study said that their new understanding of how anaesthetics induce sleep could lead to new anaesthetics providing a better recovery for patients.

"Individuals need a prolonged period of deep sleep to gain its restorative benefits. Patients recovering from surgery and those in intensive care often suffer from sleep-deprivation. Our research might lead to the design of anaesthetics that mimic non-REM sleep more accurately, reducing post-operative fatigue," said Professor Maze.

The research was supported by the Medical Research Council (UK), the Westminster Medical Trust (UK) and the National Institutes of Health (USA).

Judith Moore | alfa
Further information:
http://www.ic.ac.uk

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 working of a molecular string phone

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.

This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.

Im Focus: Milestones on the Way to the Nuclear Clock

Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. TU Wien (Vienna) is part of both teams.

If you want to build the most accurate clock in the world, you need something that "ticks" very fast and extremely precise. In an atomic clock, electrons are...

Im Focus: Graphene sets the stage for the next generation of THz astronomy detectors

Researchers from Chalmers University of Technology have demonstrated a detector made from graphene that could revolutionize the sensors used in next-generation space telescopes. The findings were recently published in the scientific journal Nature Astronomy.

Beyond superconductors, there are few materials that can fulfill the requirements needed for making ultra-sensitive and fast terahertz (THz) detectors for...

Im Focus: Physicists from Stuttgart prove the existence of a supersolid state of matte

A supersolid is a state of matter that can be described in simplified terms as being solid and liquid at the same time. In recent years, extensive efforts have been devoted to the detection of this exotic quantum matter. A research team led by Tilman Pfau and Tim Langen at the 5th Institute of Physics of the University of Stuttgart has succeeded in proving experimentally that the long-sought supersolid state of matter exists. The researchers report their results in Nature magazine.

In our everyday lives, we are familiar with matter existing in three different states: solid, liquid, or gas. However, if matter is cooled down to extremely...

Im Focus: World record for tandem perovskite-CIGS solar cell

A team headed by Prof. Steve Albrecht from the HZB will present a new world-record tandem solar cell at EU PVSEC, the world's largest international photovoltaic and solar energy conference and exhibition, in Marseille, France on September 11, 2019. This tandem solar cell combines the semiconducting materials perovskite and CIGS and achieves a certified efficiency of 23.26 per cent. One reason for this success lies in the cell’s intermediate layer of organic molecules: they self-organise to cover even rough semiconductor surfaces. Two patents have been filed for these layers.

Perovskite-based solar cells have experienced an incredibly rapid increase in efficiency over the last ten years. The combination of perovskites with classical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

AI for Laser Technology Conference: optimizing the use of lasers with artificial intelligence

29.08.2019 | Event News

 
Latest News

Low sea-ice cover in the Arctic

13.09.2019 | Earth Sciences

Researchers produce synthetic Hall Effect to achieve one-way radio transmission

13.09.2019 | Power and Electrical Engineering

Penn engineers' new topological insulator reroutes photonic 'traffic' on the fly

13.09.2019 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>