Nav: Home

Zebrafish research highlights role of locus coeruleus in anesthesia

September 18, 2018

The application of general anesthesia in clinical therapy has been an indispensable part of modern medicine for more than a century. However, due to the complexity of the brain and the extensive actions of general anesthetic drugs, neural mechanisms underlying general anesthesia have remained a mystery.

Recently, Dr. DU Jiulin's lab at the Institute of Neuroscience of the Chinese Academy of Sciences and Prof. YU Tian's team at Zunyi Medical College used a larval zebrafish model to explore this mystery. Their research revealed that two commonly used intravenous anesthetic drugs, propofol and etomidate, suppress the excitability of locus coeruleus (LC) neurons via synergic mechanisms - thus inhibiting presynaptic excitatory inputs and inducing membrane hyperpolarization of these cells.

This study, which was published in Cell Reports on September 18, shows that the locus coeruleus-norepinephrine (LC-NE) system plays a modulatory role in both the induction of and emergence from intravenous general anesthesia.

The LC nucleus is a main site for synthesizing NE in the brain. Recent studies have shown that activation of the LC-NE system in mice facilitates behavioral arousal from inhalational isoflurane-induced anesthesia. In contrast, inhibition of this system causes hypersensitive induction to and delayed the recovery from anesthesia induced by inhalational anesthetics.

However, understanding the role of intravenous anesthetics on the LC-NE system and the synaptic mechanisms involved remained rudimentary.

To better understand the action of intravenous anesthetics, researchers first established an anesthesia zebrafish model via bath application of two intravenous anesthetic drugs, propofol and etomidate. The researchers determined the state of general anesthesia by examining the animal's spontaneous locomotion as well as electrical activity of the brain and spinal nerves.

They then found that local lesion of LC neurons via two-photon laser-based ablation or genetic depletion of NE synthesis accelerated the induction of general anesthesia and retarded emergence from general anesthesia.

Mechanistically, in vivo whole-cell recording revealed that both of the anesthetics used in the study suppress LC neuronal activity through a cooperative mechanism: They inhibit presynaptic excitatory inputs and induce GABAA receptor-mediated hyperpolarization of these neurons.

These results show that the LC-NE system contributes to both the induction of and emergence from intravenous general anesthesia via a cooperative mechanism. The study also highlights the usefulness of the larval zebrafish model for studying neural mechanisms of general anesthesia.
-end-


Chinese Academy of Sciences Headquarters

Related Brain Articles:

Human brain size gene triggers bigger brain in monkeys
Dresden and Japanese researchers show that a human-specific gene causes a larger neocortex in the common marmoset, a non-human primate.
Unique insight into development of the human brain: Model of the early embryonic brain
Stem cell researchers from the University of Copenhagen have designed a model of an early embryonic brain.
An optical brain-to-brain interface supports information exchange for locomotion control
Chinese researchers established an optical BtBI that supports rapid information transmission for precise locomotion control, thus providing a proof-of-principle demonstration of fast BtBI for real-time behavioral control.
Transplanting human nerve cells into a mouse brain reveals how they wire into brain circuits
A team of researchers led by Pierre Vanderhaeghen and Vincent Bonin (VIB-KU Leuven, Université libre de Bruxelles and NERF) showed how human nerve cells can develop at their own pace, and form highly precise connections with the surrounding mouse brain cells.
Brain scans reveal how the human brain compensates when one hemisphere is removed
Researchers studying six adults who had one of their brain hemispheres removed during childhood to reduce epileptic seizures found that the remaining half of the brain formed unusually strong connections between different functional brain networks, which potentially help the body to function as if the brain were intact.
Alcohol byproduct contributes to brain chemistry changes in specific brain regions
Study of mouse models provides clear implications for new targets to treat alcohol use disorder and fetal alcohol syndrome.
Scientists predict the areas of the brain to stimulate transitions between different brain states
Using a computer model of the brain, Gustavo Deco, director of the Center for Brain and Cognition, and Josephine Cruzat, a member of his team, together with a group of international collaborators, have developed an innovative method published in Proceedings of the National Academy of Sciences on Sept.
BRAIN Initiative tool may transform how scientists study brain structure and function
Researchers have developed a high-tech support system that can keep a large mammalian brain from rapidly decomposing in the hours after death, enabling study of certain molecular and cellular functions.
Wiring diagram of the brain provides a clearer picture of brain scan data
In a study published today in the journal BRAIN, neuroscientists led by Michael D.
Blue Brain Project releases first-ever digital 3D brain cell atlas
The Blue Brain Cell Atlas is like ''going from hand-drawn maps to Google Earth'' -- providing previously unavailable information on major cell types, numbers and positions in all 737 brain regions.
More Brain News and Brain Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Warped Reality
False information on the internet makes it harder and harder to know what's true, and the consequences have been devastating. This hour, TED speakers explore ideas around technology and deception. Guests include law professor Danielle Citron, journalist Andrew Marantz, and computer scientist Joy Buolamwini.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.