Navigation Links
Stimulation of brain region restores consciousness to animals under general anesthesia
Date:7/28/2014

Stimulating one of two dopamine-producing regions in the brain was able to arouse animals receiving general anesthesia with either isoflurane or propofol. In the August issue of Anesthesiology, investigators from Massachusetts General Hospital (MGH) report that rats anesthetized with continuous doses of either agent would move, raise their heads and even stand up in response to electrical stimulation delivered to the ventral tegmental area (VTA). Stimulation of the other major dopamine-releasing area, the substantia nigra, did not induce the animals to wake up.

"Dopamine cells in the VTA are involved in cognition, motivation and reward, while cells in the substantia nigra are important for movement; and our results showed that VTA cells may also be involved in dopamine's known arousal function." explains Ken Solt, MD, of the MGH Department of Anesthesia, Critical Care and Pain Medicine, corresponding author of the report. "Clinically, emergence from general anesthesia is still a passive process during which we just wait for the drugs to wear off and the patient to wake up, a process that can take from a few minutes to an hour or longer. Finding a way to safely arouse patients from anesthesia could both improve operating room efficiency and, even more importantly, may reduce problems such as postoperative delirium and cognitive dysfunction."

Previous studies by Solt and his colleagues have shown that administration of the stimulant drug methylphenidate (Ritalin), known to enhance dopamine-mediated neurotransmission, aroused animals receiving general anesthesia with either inhaled isoflurane or intravenous propofol. An additional study found that activating dopamine receptors also induced reanimation in anesthetized animals, but since older evidence implied that dopamine had no significant role in maintaining wakefulness, the MGH team designed the current study to investigate more directly the role of the brain's major dopamine-releasing structures in emergence from anesthesia.

Tiny electrodes were placed in either the VTA or the substantia nigra of anesthetized rats. Application of a mild electric current stimulates only the tissues directly adjacent to the electrodes, inducing dopamine release. Both groups of animals received continuous isoflurane anesthesia at a dose sufficient to maintain unconsciousness; but while electrical stimulation of the VTA successfully reanimated all animals in which electrodes were correctly positioned, stimulation of the substantia nigra produced no arousal response. Several days later the experiment was repeated using propofol in the animals that had reanimated with VTA stimulation, and again VTA stimulation restored conscious behaviors. A subsequent experiment showed that EEG recordings from anesthetized animals shifted to patterns associated with arousal in response to stimulation of the VTA but not to substantia nigra stimulation.

"These results suggest that the results of our methylphenidate studies were produced by increased dopamine release from the VTA," says Solt, an assistant professor of Ansthesia at Harvard Medical School. "Now we need to investigate the specific role of dopamine neurons and whether activating those cells could help prevent or treat postoperative problems."


'/>"/>

Contact: Terri Ogan
togan@partners.org
617-726-0954
Massachusetts General Hospital
Source:Eurekalert

Related medicine news :

1. Low strength brain stimulation may be effective for depression
2. Deep brain stimulation improves non motor symptoms in Parkinsons disease
3. Tendon stimulation the key to repair in tennis elbow
4. Rice researcher rebooting deep brain stimulation
5. What is being said in the media and academic literature about neurostimulation?
6. Deep brain stimulation for obsessive-compulsive disorder releases dopamine in the brain
7. Precise brain mapping can improve response to deep brain stimulation in depression
8. Functional electrical stimulation improves neuronal regeneration after cerebral infarction
9. New stroke research combines brain stimulation, gait training
10. Knellinger Dental Excellence Brings Laser Gum Disease Treatment for Bone Stimulation and Possible Tooth Loss Prevention
11. Parkinsons disease patients following subthalamic nucleus deep brain stimulation: fully understanding of social maladjustment
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/30/2017)... ... March 30, 2017 , ... An inventor and manicurist from Greet, S.C., wants to ... I try to help customers maintain clean and healthy feet, so I know the importance ... their feet at home, I designed the FOOT-TRAN SYSTEM." , The FOOT-TRAN SYSTEM enables a ...
(Date:3/29/2017)... ... March 29, 2017 , ... During the last week ... free screening colonoscopies to eligible individuals in the local community. , Colon cancer ... regular screenings can detect colon cancer while it is small, confined and easier to ...
(Date:3/29/2017)... ... March 29, 2017 , ... Full Contact K9, an Atlanta-based ... Pet Protect Law that assists dog owners in creating legally-enforceable pet trusts for ... taking the natural next step to protect their new companion. Says Evan Dunbar, CEO ...
(Date:3/29/2017)... Petersburg, FL (PRWEB) , ... March 30, 2017 , ... ... called the "Spice of Life" or "Wonder Spice", it has been used for thousands ... use in the East," says Heshelow, author of " Turmeric: How to Use it ...
(Date:3/29/2017)... ... March 29, 2017 , ... The Wall Centre ... to new patients from Burnaby, BC. Patients in need of experienced orthodontics, laser ... can see the esteemed team at Wall Centre Dental. Drs. Parviz Roshan, Siamak ...
Breaking Medicine News(10 mins):
(Date:3/29/2017)... Mar. 29, 2017 Research and Markets ... Market Size & Forecast By Type (Insource IONM, Outsource IONM), ... report to their offering. ... The global Intraoperative Neuromonitoring (IONM) market ... intraoperative neuromonitoring market is anticipated to witness significant growth in ...
(Date:3/29/2017)... , Mar. 29, 2017 Research and Markets ... Market 2017-2021" report to their offering. ... The global energy-based aesthetic devices market ... The report, Global Energy-Based Aesthetic Devices Market 2017-2021, ... from industry experts. The report covers the market landscape and its ...
(Date:3/29/2017)... SAN DIEGO , March 29, 2017 Avelas Biosciences, ... care from diagnosis through treatment, today announced that Carmine N. ... of the company at the Needham & Company 16 th ... EDT (8:20 a.m. PDT) at the Westin Grand Central Hotel in ... Biosciences ...
Breaking Medicine Technology: