Navigation Links
Woodchucks and sudden cardiac death
Date:2/23/2012

San Diego, Calif. How much calcium could a hibernating woodchuck's heart cells sequester, if a hibernating woodchuck's heart cells could sequester calcium? More than enough, it turns out, to protect the animals from cardiac arrhythmias abnormal heart rhythms such as ventricular tachycardia and ventricular fibrillation that can lead to sudden cardiac death according to a new study of the hibernating animals that may provide insight into arrhythmia therapies. The findings will be presented at a poster session at the 56th Annual Meeting of the Biophysical Society (BPS), which will take place Feb. 25-29 in San Diego, Calif.

Bear and bats can be roused from their slumber by external stimuli. But woodchucks (Marmota monax), also known as groundhogs, are "true hibernators," which means they can enter a profoundly altered physiological state: their body temperature drops to near-ambient levels (often as low as freezing) and heart and respiration rates slow dramatically. Despite or perhaps because of these changes, hibernating animals have been found to be more resistant to cardiac arrhythmias and sudden cardiac death.

Electrophysiologist Lai-Hua Xie, an assistant professor at the University of Medicine and Dentistry of New Jersey (UMDNJ)-New Jersey Medical School in Newark, and his colleagues examined muscle cells, or myocytes, isolated in winter and in summer from woodchucks. Using a charge-coupled device (CCD) camera, the researchers monitored the release and uptake of calcium ions when the cells were activated. The team found that in winter woodchucks, the myocyte sarcoplasmic reticulum the membrane system in muscle cells that stores and releases calcium had less spontaneous leakage of calcium, released more of it during excitation, and took it back up faster than that of summer woodchucks or non-hibernating animals. This is likely, he says, "to generate a stronger contraction and faster relaxation, and most importantly, to prevent abnormal changes in the heart's electrical activities called afterdepolarizations."

The overall effect, Xie says, is a "higher resistance to arrhythmia in woodchucks in winter. Understanding these cardiac adaptive mechanisms in hibernators may suggest new strategies to protect non-hibernating animals, especially humans, from fatal cardiac arrhythmias induced by hypothermic stresses and myocardial ischemia."

Xie and his colleagues conducted the work with funding from the National Institutes of Health and in collaboration with Stephen Vatner, director of the UMDNJ-New Jersey Medical School Cardiovascular Research Center.

The presentation, "Calcium handling properties in a hibernating animal: Insights into antiarrhythmic mechanisms," is at 1:45 on Sunday, Feb. 26, 2012, in the San Diego Convention Center, Hall FGH. ABSTRACT: http://tinyurl.com/7mtrp4a


'/>"/>

Contact: Ellen R. Weiss
eweiss@biophysics.org
240-290-5606
American Institute of Physics
Source:Eurekalert

Related biology news :

1. OHSU discovery may someday lead to prevention and treatment of sudden infant death syndrome
2. Johns Hopkins researchers identify new genetic risk factor for sudden cardiac death
3. Comprehensive report on sudden oak death
4. New report suggests why risk for sudden infant death syndrome is greater in babies of mothers who smoke
5. Researchers nationwide ask for new focus on sudden death heart disorder
6. Gene mingling increases sudden death risk
7. Comprehensive cardiogenetic testing for families of sudden unexplained death victims can save lives
8. Some short-term memories die suddenly, no fading
9. Common gene variants influence risk factor for sudden cardiac death
10. Genetic risk factors identified for sudden cardiac death
11. Hopkins scientists ID 10 genes associated with a risk factor for sudden cardiac death
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/8/2016)...   Valencell , the leading innovator in ... secured $11M in Series D financing. The investment ... fund being launched by UAE-based financial services company ... TDF Ventures and WSJ Joshua Fund. Valencell plans ... growth and accelerate its pioneering innovation in accurate ...
(Date:3/3/2016)... DE SOTO, Kansas , March 3, ... Plus® to offer Oncimmune,s Early CDT®-Lung, a blood ... detection of lung cancer Early CDT®-Lung test ... individuals. --> Early CDT®-Lung test to its ... --> Oncimmune, a leader in early cancer detection, ...
(Date:3/1/2016)... March 1, 2016 ... addition of the  "Global Biometric Access ... to their offering. --> ... of the  "Global Biometric Access Control ... their offering. --> Research ...
Breaking Biology News(10 mins):
(Date:5/3/2016)... ... 03, 2016 , ... Morf Media Inc ., developer ... on mobile devices, today released a new interactive Food and Drug Administration ... course is essential for owners or operators of places of business that are ...
(Date:5/3/2016)... , ... May 03, 2016 , ... ... the addition of Dr. Nancy Gillett to its Board of Directors. Dr. Gillett ... served as Corporate Executive Vice President and Chief Scientific Officer. A board-certified veterinary ...
(Date:5/3/2016)... 2016 - And Other Rising ... of Those Competitor Biologics  - Biosimilar Drug ... Prospects ,  Who are the most important ... are their sales potentials? Discover, in our updated survey, ... opportunities and revenue forecasting. Visiongain,s ...
(Date:5/3/2016)... ... May 03, 2016 , ... ... clinics and IVF laboratories. A contingency of reproductive endocrinologists, including Dr. George ... women experiencing infertility and to help them build families. , Ovation Fertility is ...
Breaking Biology Technology: