Navigation Links
Study offers new insights into the mechanics of muscle fatigue
Date:1/17/2013

A study in The Journal of General Physiology examines the consequences of muscle activity with surprising results, indicating that the extracellular accumulation of potassium that occurs in working muscles is considerably higher than previously thought.

Muscle excitation involves the influx of sodium ions and efflux of potassium ions. Although the fraction of ions that cross the muscle membrane with each contraction is minute, repeated activity can lead to substantial changes in the intracellular and extracellular concentrations of sodium and potassium ions. The extent of these changes, however, has been unclear. Now, Torben Clausen from Aarhus University in Denmark provides quantitative analyses of the changes in intracellular and extracellular ion concentration resulting from stimulation of a leg muscle in rats, providing insight into how they vary with muscle activity.

Clausen measured the changes in concentration of sodium, potassium, and chloride ions in working rat extensor digitorum longus (ESL) muscles. Remarkably, when their muscles were stimulated to fire at a rate of 5 Hz (comparable to that in the legs of a person riding a bicycle) for five minutes, sufficient intracellular potassium was lost to lead to an extracellular concentration that would interfere with further excitation. These results suggest that accumulation of extracellular potassium is a much larger contributor to muscle fatigue than previously thought, which may be of particular importance in such conditions as hyperkalemic periodic paralysis and other channelopathies that affect skeletal muscle. These changes in ion distribution are opposed through the action of the "Na+/K+ pump"which expends energy to move sodium out of the cell and potassium into itand will therefore be even more pronounced under disease- and injury-related conditions associated with decreased pump activity.


'/>"/>

Contact: Rita Sullivan King
news@rupress.org
212-327-8603
Rockefeller University Press
Source:Eurekalert

Related biology news :

1. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
2. Law that regulates shark fishery is too liberal: UBC study
3. New study will help protect vulnerable birds from impacts of climate change
4. Study jointly led by UCSB researcher supports theory of extraterrestrial impact
5. BYU study: Using a gun in bear encounters doesnt make you safer
6. 15-year study: When it comes to creating wetlands, Mother Nature is in charge
7. Pycnogenol (French maritime pine bark extract) shown to improve menopause symptoms in new study
8. Crystal structure of archael chromatin clarified in new study
9. EU-funded study underlines importance of Congo Basin for global climate and biodiversity
10. University of Houston study shows BP oil spill hurt marshes, but recovery possible
11. Study demonstrates cells can acquire new functions through transcriptional regulatory network
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/6/2017)... March 6, 2017 Mintigo , ... today announced Predictive Sales Coach TM , its ... sales intelligence into Salesforce. This unique AI application ... sales organizations with deep knowledge of their customers ... intelligent engagement. Predictive Sales Coach extends Mintigo,s existing ...
(Date:3/2/2017)... Who risk to be deprived of its ... report: https://www.reportbuyer.com/product/4313699/ WILL APPLE AND SAMSUNG ... Fingerprint sensors using capacitive technology represent a fast growing ... forecasts an increase of 360% of the number of ... fingerprint sensor market between 2014 and 2017 (source : ...
(Date:2/28/2017)... 2017   Acuant , a leading provider of ... enhancements to new and core technologies building upon the ... mobile and desktop Acuant FRM TM facial recognition ... real time manual review of identity documents by accredited ... fastest and most accurate capture software to streamline workflows ...
Breaking Biology News(10 mins):
(Date:3/27/2017)... DUBLIN , March 27, 2017 ... access to a comprehensive library of reports on Valero ... the transportation fuels and petrochemical industries. ...      (Logo: http://photos.prnewswire.com/prnh/20160330/349511LOGO) ... is biofuel production to go green. Ethanol today, even though ...
(Date:3/27/2017)... Israel , March 27, 2017 DarioHealth ... with mobile health and big data solutions, today announced ... party insurance coverage option for U.S. consumers who want ... DarioHealth has signed strategic alliance agreements with ... verify insurance coverage benefits, and if approved, will supply ...
(Date:3/24/2017)... 2017 Research and Markets has announced the ... Global Strategic Business Report" report to their offering. ... This report analyzes the ... Million. Annual estimates and forecasts are provided for the period 2014 ... secondary research. The report profiles 25 companies including ...
(Date:3/24/2017)... 24, 2017 Agenus Inc. (NASDAQ: AGEN), an ... and cancer vaccines, today announced participation at the following ... William Blair and Maidstone Life Sciences conference "Cancer Immunotherapy ... New York, NY . Agenus will ... at 9:40 am: Robert B. Stein , M.D., ...
Breaking Biology Technology: