Navigation Links
Exercise protects the heart via nitric oxide
Date:5/4/2011

Exercise both reduces the risk of a heart attack and protects the heart from injury if a heart attack does occur. For years, doctors have been trying to dissect how this second benefit of exercise works, with the aim of finding ways to protect the heart after a heart attack.

Researchers at Emory University School of Medicine have identified the ability of the heart to produce and store nitric oxide as an important way exercise protects the heart from injury.

Nitric oxide, a short-lived gas generated within the body, turns on chemical pathways that relax blood vessels to increase blood flow and activate survival pathways. Both the chemical nitrite and nitrosothiols, where nitric oxide is attached to proteins via sulfur, appear to act as convertible reservoirs for nitric oxide in situations where the body needs it, such as a lack of blood flow or oxygen.

The Emory team's results, published online in the journal Circulation Research, strengthen the case for nitrite and nitrosothiols as possible protectants from the damage of a heart attack.

The first author is John Calvert, PhD, assistant professor of surgery at Emory University School of Medicine. The senior author is David Lefer, PhD, professor of surgery at Emory University School of Medicine and director of the Cardiothoracic Research Laboratory at Emory University Hospital Midtown. Collaborators included scientists at University of Colorado, Boulder, and Johns Hopkins University.

"Our study provides new evidence that nitric oxide generated during physical exercise is actually stored in the bloodstream and heart in the form of nitrite and nitrosothiols. These more stable nitric oxide intermediates appear to be critical for the cardioprotection against a subsequent heart attack," Lefer says.

Timing is key the benefits of exercise don't last In experiments with mice, the researchers showed that four weeks of being able to run on a wheel protected them from having a coronary artery was blocked; the amount of heart muscle damaged by the blockage was less after the exercise period. Importantly, the mice are still protected a week after the wheel is taken away.

The researchers found that voluntary exercise boosted levels of an enzyme that produces nitric oxide (eNOS, endothelial nitric oxide synthase). Moreover, the levels of eNOS in heart tissue, and nitrite and nitrosothiols in the blood as well as heart tissue, stayed high for a week after exercise ceased, unlike other heart enzymes stimulated by exercise. The protective effects of exercise did not extend beyond four weeks after the exercise period was over, when nitrite and nitrosothiols in the heart returned to baseline.

In mice that lack the eNOS enzyme, exercise did not protect the heart from a coronary blockage, although these mice appeared to lack the ability to exercise as much as normal mice.

Another molecule that appears to be important for the benefits of exercise is the beta-3-adrenergic receptor, which allows cells to respond to the hormones epinephrine and norepinephrine. All of the beneficial effects of voluntary exercise are lost in mice that are deficient in this receptor. One of the effects of stimulating the receptor appears to be activating eNOS. Additional animal studies are currently underway in Lefer's lab to determine the potential benefit of beta-3-adrenergic receptor activating drugs following a heart attack.


'/>"/>

Contact: Jennifer Johnson
jennifer.johnson@emory.edu
404-727-5696
Emory University
Source:Eurekalert

Related medicine news :

1. Structured Exercise Programs Help Lower Blood Sugar, Study Finds
2. Study finds diet plus exercise is more effective for weight loss than either method alone
3. Aerobic Exercise May Curb Non-Alcoholic Fatty Liver Disease: Report
4. Low-Intensity Exercise, Drug Combo Can Help Parkinsons Patients, Studies Show
5. Short Bursts of Exercise Good for the Heart: Study
6. Dangerous blood pressure increases during exercise can be blocked, UT Southwestern researchers find
7. Exercise may prevent stress on telomeres, a measure of cell health
8. Exercise Is Key for People With Arthritis: Expert
9. Diet-Exercise Combo Seems to Work Best for Obese Seniors
10. Lack of motivation, equipment main barriers for exercise for boys
11. Exercise May Blunt Salts Effect on Hypertension
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/28/2017)... ... 2017 , ... The Radiology Business Management Association (RBMA) is pleased ... new executive director. Mr. Still was selected through a careful months-long search by the ... is known to our members, has been a part of building the RBMA since ...
(Date:3/28/2017)... , ... March 28, 2017 , ... With less than ... acne, access to quality care can be limited while the desire to conquer breakouts ... customized prescription acne care for every customer online, today released its inaugural survey on ...
(Date:3/28/2017)... ... March 28, 2017 , ... A minimally invasive porcelain ... smile.” The National Association of Dental Laboratories (NADL) is informing dentists about the ... of when utilizing dental laboratories and technicians that create these veneers. , ...
(Date:3/28/2017)... ... ... With expansion and efficiency in mind, Patten Seed Company completed relocation of ... opened in Marshallville in 2006, and a bagging and shipping facility has been in ... Patten Seed operations to the Middle Georgia location from their previous home in Lakeland, ...
(Date:3/28/2017)... ... ... Prophets Bones”: a thrilling adventure that reveals the mystery of Kevin’s purpose. “A Prophets Bones” ... and teachers had asked of him that he had neglected to do, but this was ... Creator. There were some who would have felt themselves to be special and better than ...
Breaking Medicine News(10 mins):
(Date:3/28/2017)... TAIPEI, Taiwan , March 28, 2017 /PRNewswire/ ... medical device company, is pleased to announce ... Series A investment of Panther Orthopedics, Inc., a ... pioneering innovative dynamic fixation solutions for orthopedic extremity ... market continues to expand rapidly, primarily due to ...
(Date:3/27/2017)... , March 27, 2017 ... better understand Eli Lilly and its partnering interests and activities ... 2010 report provides an in-depth insight into the partnering activity ... On demand company reports are prepared upon purchase to ... company data. The report will be delivered in ...
(Date:3/27/2017)... March 27, 2017  Cryoport, Inc. (NASDAQ: CYRX, CYRXW) ... to offer shares of common stock in an underwritten ... file with the Securities and Exchange Commission (the "SEC"). ... and there can be no assurance as to whether ... to the actual size or terms of the offering. ...
Breaking Medicine Technology: