Navigation Links
Penn study sheds light on how the brain shifts between sleep/awake states under anesthesia

(PHILADELPHIA) Despite the fact that an estimated 25 million patients per year in the U.S. undergo surgeries using general anesthesia, scientists have only been able to hypothesize exactly how anesthetics interact with the central nervous system. They previously thought that the processes of "going under" and waking up from anesthesia affected the brain in the same way. Now, researchers at the University of Pennsylvania School of Medicine have established in animal models that the brain comes in and out of a state of induced unconsciousness through different processes. The findings, published in PLoS One, may help researchers better understand serious sleep disorders and states of impaired consciousness such as comas.

"One major unanswered question in neuroscience is how the brain transitions between conscious and unconscious states," said senior author Max B. Kelz, MD, PhD, assistant professor of Anesthesiology and Critical Care. "Our results suggest that the brain keeps track of whether it is conscious or offline in an unconscious state. We are working to understand the mechanisms through which the brain accomplishes this feat. Studying general anesthetics in animal models offers a controllable means to investigate this newly recognized behavioral barrier that separates conscious from unconscious states."

Induction of anesthesia is commonly attributed to drug-induced modifications of neuronal function, whereas emergence from anesthesia has been thought to occur passively, with the elimination of the anesthetic from sites in the central nervous system (CNS). If this were true, then CNS anesthetic concentrations on induction and emergence would be indistinguishable.

However, by generating anesthetic dose response data in both fruit flies and mice, the researchers demonstrated that the forward and reverse paths through which anesthetic-induced unconsciousness arises and dissipates are not identical. Instead the animal subjects exhibited a delay in return to a state of consciousness despite the reduced concentration of the anesthetic.

The researchers observed that once a group of animal subjects underwent a transition from wakefulness to anesthetic-induced unconsciousness, the subjects exhibited resistance to the return of the wakeful state. Based on their findings, the authors propose a fundamental and biologically conserved state, which they call neural inertia, a tendency of the CNS to resist transitions between consciousness and unconsciousness.

"The findings from this study may provide insights into the regulation of sleep as well as states in which return of consciousness is pathologically impaired such as some types of coma," said Kelz. "This line of research may one day help us to develop novel anesthetic drugs and targeted therapies for patients who have different forms of sleep disorders or who have the potential to awaken from coma but remain stuck in comatose states for months or years."


Contact: Jessica Mikulski
University of Pennsylvania School of Medicine

Related medicine news :

1. Study Links Gene to Serious Eye Disease
2. Study Suggests Statins Could Help Some With Normal Cholesterol
3. Heart Risks the Same With 2 Diabetes Drugs: Study
4. Mayo researchers develop new laboratory cell lines to study treatment for ATC
5. Herpes Drugs Wont Raise Birth Defect Risk, Study Finds
6. Mumps vaccine coverage should be improved, study finds
7. Study Suggests Link Between Diet Sodas, Preterm Delivery
8. Study suggests oxytocin makes people trusting, but not gullible
9. University of Colorado Denver Business School study shows failure better teacher than success
10. New study: More than 20,000 sledding injuries each year
11. Study of cell division sheds light on special mechanism in egg cells
Post Your Comments:
(Date:11/25/2015)... ... 2015 , ... The holiday season is jam-packed with family ... of attendees is of the utmost importance. Whether you are cooking at home ... recipes a try this holiday season. , Turkey Croquettes ,     Ingredients: ...
(Date:11/25/2015)... ... 2015 , ... Ministers, senior government and UN agencies, representatives ... of Excellence, and public R&D institutions, civil societies and other partners gathered today ... African Network for Drugs and Diagnostics Innovation, ANDI, Stakeholders Meeting. The three- day ...
(Date:11/25/2015)... ... 25, 2015 , ... Dental professionals who would like to become more proficient ... attend Dr. Mark Iacobelli’s Advanced Implant Mentoring (AIM) CE course. Courses will be held ... the co-founders of Advanced Implant Mentoring (AIM), Dr. Iacobelli and Dr. D’Orazio are proud ...
(Date:11/25/2015)... ... November 25, 2015 , ... Smiles by Stevens ... Bruxism, and moderate facial wrinkling. While many patients are aware of the benefits of ... success Botox® delivers to those suffering with discomfort, soreness, and pain as a result ...
(Date:11/25/2015)... , ... November 25, 2015 , ... “While riding the ... inventor, from Bronx, N.Y. “I thought there had to be a convenient and comfortable ... PROTECTOR. , The PROTECTOR enables disabled individuals to safely travel during cold or inclement ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... 3D bioprinting market is expected ... new report by Grand View Research Inc. Rising prevalence of ... kidney transplantation is expected to boost the market growth, as ... transplantation. --> 3D bioprinting market is expected ... new report by Grand View Research Inc. Rising prevalence of ...
(Date:11/26/2015)... , November 26, 2015 ... the addition of the  "2016 Future ... Global Cell Surface Testing Market: Supplier ... to their offering.  --> ... of the  "2016 Future Horizons and ...
(Date:11/26/2015)... Research and Markets ( ) has ... Market by Type (Dressings, Therapy Devices, Active Wound Care), ... Facility), and Geography - Global Forecast to 2020" ... --> The purpose of this report ... the global advanced wound care market. It involves deep ...
Breaking Medicine Technology: