Featured Research

from universities, journals, and other organizations

Cardiac muscle really knows how to relax: Potential cardio-protective mechanism in heart

Date:
April 21, 2011
Source:
Cell Press
Summary:
New insight into the physiology of cardiac muscle may lead to the development of therapeutic strategies that exploit an inherent protective state of the heart. The research discovers a state of cardiac muscle that exhibits a low metabolic rate and may help to regulate energy use and promote efficiency in this hard-working and vital organ.

New insight into the physiology of cardiac muscle may lead to the development of therapeutic strategies that exploit an inherent protective state of the heart. The research, published online on April 19th in the Biophysical Journal, discovers a state of cardiac muscle that exhibits a low metabolic rate and may help to regulate energy use and promote efficiency in this hard-working and vital organ.

Related Articles


Muscle cells are highly specialized cells that are able to physically contract and produce force. Many variables contribute to the active generation of force, with the availability of calcium in the cell interior playing a major role in the process of muscle contraction. However, recent studies have also implicated the state of a key contractile protein called myosin. Myosin is a motor protein that binds to another contractile protein (called actin) and, using energy it liberated from ATP, pulls on the actin to physically shorten the muscle.

"We have recently identified a new 'super' relaxed state of myosin in resting skeletal muscle, called the SRX," says senior study author, Dr. Roger Cooke from the University of California, San Francisco. "The SRX state has a much smaller ATP turnover rate and shows that "relaxed" myosin comes in at least two states that differ with regards to energy utilization. By analogy with another motor, active myosin generating force is akin to a car racing down the road. The normal relaxed myosin is similar to a car stopped at a traffic light with the motor running, and the counterpart of the SRX is a car parked beside the road with the motor off. In the current study, we sought to build on our earlier work in skeletal muscle and examine the SRX state in cardiac muscle cells."

Dr. Cooke's group showed that there is an SRX state in resting cardiac muscle cells that is similar to the SRX state in resting skeletal muscle cells. The researchers went on to show that when you look at active muscle, the SRX state is quite different in cardiac muscle compared to skeletal muscle. "We observed a rapid transition of myosin out of the SRX state in active skeletal muscle cells, while, somewhat surprisingly, the SRX state was maintained in active cardiac muscle cells," says Dr. Cooke. This suggests that the SRX plays a very different role in these different types of muscle.

"We identified a new state of myosin in cardiac muscle with a very low ATP turnover rate that could play a role in decreasing the metabolic load of the myocardium," explains Dr. Cooke. "The mechanism proposed here for cardiac muscle suggests that therapeutic interventions that increase the population of the SRX would be cardio-protective during times of stress. They may also be useful in preserving organs for transplant."


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Journal Reference:

  1. pleuni Hooijman, Melanie A. Stewart and Roger Cooke. A New State of Cardiac Myosin with Very Slow ATP Turnover: A Potential Cardioprotective Mechanism in the Heart. Biophysical Journal, Volume 100, Issue 8, 1969-1976, 20 April 2011 DOI: 10.1016/j.bpj.2011.02.061

Cite This Page:

Cell Press. "Cardiac muscle really knows how to relax: Potential cardio-protective mechanism in heart." ScienceDaily. ScienceDaily, 21 April 2011. <www.sciencedaily.com/releases/2011/04/110419121344.htm>.
Cell Press. (2011, April 21). Cardiac muscle really knows how to relax: Potential cardio-protective mechanism in heart. ScienceDaily. Retrieved March 6, 2015 from www.sciencedaily.com/releases/2011/04/110419121344.htm
Cell Press. "Cardiac muscle really knows how to relax: Potential cardio-protective mechanism in heart." ScienceDaily. www.sciencedaily.com/releases/2011/04/110419121344.htm (accessed March 6, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, March 6, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Bupa Eyes India Healthcare Opportunities

Bupa Eyes India Healthcare Opportunities

Reuters - Business Video Online (Mar. 5, 2015) Bupa is hoping to expand in India&apos;s fast-growing health insurance market, once a rule change on foreign investment is implemented. The British private healthcare group&apos;s CEO tells Grace Pascoe why it&apos;s so keen on the new opportunity. Video provided by Reuters
Powered by NewsLook.com
Doctor in Your Pocket Is Getting Smarter

Doctor in Your Pocket Is Getting Smarter

Reuters - Business Video Online (Mar. 5, 2015) Mobile apps are turning smartphones into a personal doctors, with users able to measure heart rate, blood pressure and even blood sugar. But will it change our behaviour? Ivor Bennett reports from the Mobile World Congress in Barcelona. Video provided by Reuters
Powered by NewsLook.com
AbbVie Inks $21B Deal To Buy Cancer Drugmaker Pharmacyclics

AbbVie Inks $21B Deal To Buy Cancer Drugmaker Pharmacyclics

Newsy (Mar. 5, 2015) AbbVie announced Wednesday it will buy cancer drugmaker Pharmacyclics in a $21 billion deal. Video provided by Newsy
Powered by NewsLook.com
Toddlers Drinking Coffee? Why You Shouldn't Share Your Joe

Toddlers Drinking Coffee? Why You Shouldn't Share Your Joe

Newsy (Mar. 5, 2015) A survey of Boston mothers and toddlers found that 15 percent of two-year-olds drink coffee and 2.5 percent of 1-year-olds. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins