Navigation Links
Sewer-gas-induced suspended animation is rapid and reversible
Date:3/24/2008

Low doses of the toxic gas responsible for the unpleasant odor of rotten eggs can safely and reversibly depress both metabolism and aspects of cardiovascular function in mice, producing a suspended-animation-like state. In the April 2008 issue of the journal Anesthesiology, Massachusetts General Hospital (MGH) reseachers report that effects seen in earlier studies of hydrogen sulfide do not depend on a reduction in body temperature and include a substantial decrease in heart rate without a drop in blood pressure.

Hydrogen sulfide is the stinky gas that can kill workers who encounter it in sewers; but when adminstered to mice in small, controlled doses, within minutes it produces what appears to be totally reversible metabolic suppression, says Warren Zapol, MD, chief of Anesthesia and Critical Care at MGH and senior author of the Anesthesiology study. This is as close to instant suspended animation as you can get, and the preservation of cardiac contraction, blood pressure and organ perfusion is remarkable.

Previous investigations into the effects of low-dose hydrogen sulfide showed that the gas could lower body temperature and metabolic rate and also improved survival of mice whose oxygen supply had been restricted. But since hypothermia itself cuts metabolic needs, it was unclear whether the reduced body temperature was responsible for the other observed effects. The current study was designed to investigate both that question and the effects of hydrogen sulfide inhalation on the cardiovascular system.

The researchers measured factors such as heart rate, blood pressure, body temperature, respiration and physical activity in normal mice exposed to low-dose (80 ppm) hydrogen sulfide for several hours. They analyzed cardiac function with electrocardiograms and echocardiography and measured blood gas levels. While some mice were studied at room temperature, others were kept in a warm environment about 98 F to prevent their body temperatures from dropping.

In all the mice, metabolic measurements such as consumption of oxygen and production of carbon dioxide dropped in as little as 10 minutes after they began inhaling hydrogen sulfide, remained low as long as the gas was administered, and returned to normal within 30 minutes of the resumption of a normal air supply. The animals heart rate dropped nearly 50 percent during hydrogen sulfide adminstration, but there was no significant change in blood pressure or the strength of the heart beat. While respiration rate also decreased, there were no changes in blood oxygen levels, suggesting that vital organs were not at risk of oxygen starvation.

The mice kept at room temperature had the same drop in body temperature seen in earlier studies, but those in the warm environment maintained normal body temperatures. The same metabolic and cardiovascular changes were seen in both groups, indicating that they did not depend on the reduced body temperature, and analyzing the timing of those changes showed that metabolic reduction actually began before body temperature dropped.

Producing a reversible hypometabolic state could allow organ function to be preserved when oxygen supply is limited, such as after a traumatic injury, says Gian Paolo Volpato, MD, MGH Anesthesiology research fellow and lead author of the study. We dont know yet if these results will be transferable to humans, so our next step will be to study the use of hydrogen sulfide in larger mammals.

Zapol adds, It could be that inhaled hydrogen sulfide will only be useful in small animals and well need to use intravenous drugs that can deliver hydrogen sulfide to vital organs to prevent lung toxicity in larger animals. Zapol is the Reginald Jenney Professor of Anaesthesia at Harvard Medical School.


'/>"/>

Contact: Sue McGreevey
smcgreevey@partners.org
617-724-2764
Massachusetts General Hospital
Source:Eurekalert

Related medicine news :

1. RxElite Registration Statement Suspended
2. Super Food Bowl Animation From NaturalNews.com Teaches Kids to Avoid Junk Foods, Pursue Natural Nutrition
3. STMicroelectronics and Veredus Laboratories Launch Markets First Lab-on-Chip for Rapid Molecular Flu Detection at Point of Need
4. Cardiums InnerCool Therapies Unit Announces Australian Distribution Agreement for CoolBlue and Rapid Blue Systems
5. Varian Announces Global Clinical Council to Develop RapidArc(TM) Cancer Treatments
6. HHS Deputy Secretary Recognizes Grand Rapids Leaders for Improving Quality and Value in Health Care
7. Harris Corporation Demonstrates Digital Signage(TM) Solutions for Dynamic, Rapid Communications within Healthcare Enterprises
8. Varian Medical Systems Announces Symposia on RapidArc Technology for Faster, More Precise Radiotherapy Treatments
9. Mybank Goes Live With Misys Equation to Support Rapid Growth and Meet Future Regulatory Requirements
10. Varian and BrainLAB Announce Rapid Uptake of Powerful and Versatile Radiosurgery Platform
11. Forsyth launches 1-of-a-kind core service to enable rapid identification of bacterial samples
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... ... of Bruton Memorial Library on June 21 due to a possible lice infestation, as reported ... head lice: the parasite’s ability to live away from a human host, and to infest ... in the event that lice have simply gotten out of control. , As lice are ...
(Date:6/25/2016)... ... June 25, 2016 , ... First Choice Emergency ... named Dr. Sesan Ogunleye, as the Medical Director of its new Mesquite-Samuell Farm facility. ... Director of our new Mesquite location,” said Dr. James M. Muzzarelli, Executive Medical Director ...
(Date:6/25/2016)... , ... June 25, 2016 , ... ... and non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as a ... area —Johnson is one of the first doctors to perform the treatment. Orthobiologics ...
(Date:6/25/2016)... , ... June 25, 2016 , ... Conventional wisdom preaches ... success. In terms of the latter, setting the bar too high can result in ... than just slow progress toward their goal. , Research from PsychTests.com ...
(Date:6/24/2016)... Marne, Michigan (PRWEB) , ... June 24, 2016 , ... ... To deal with these feelings, many turn to unhealthy avenues, such as drug or ... Center of Marne, Michigan, has released tools for healthy coping following a traumatic event. ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016  Astellas today announced the establishment of Astellas Farma Colombia (AFC), a new affiliate ... in Latin America . ... ... ... ...
(Date:6/23/2016)... 23, 2016 The vast majority of dialysis ... facility.  Treatments are usually 3 times a week, with ... including travel time, equipment preparation and wait time.  This ... grueling for patients who are elderly and frail.  Many ... and rehabilitation centers for some duration of time. ...
(Date:6/23/2016)... June 23, 2016 The Biotechnology ... continues to present great opportunities to investors. Stock-Callers.com assesses ... Intrexon Corp. (NYSE: XON ), Vertex Pharmaceuticals ... (NASDAQ: ARNA ), and Regeneron Pharmaceuticals Inc. ... stocks and receive your complimentary trade alerts at: ...
Breaking Medicine Technology: