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:7/26/2017)... (PRWEB) , ... July 26, 2017 , ... Six greater Bay Area roller derby leagues ... “Make ‘em Bleed,” the most widely attended series of blood drives in California, beginning July ... blood over the past 4 years -- enough to have helped to save up to ...
(Date:7/26/2017)... (PRWEB) , ... July 26, ... ... for Pharmaceutical Engineering (ISPE) will host its 2017 Process Validation and ... concurrent events offer comprehensive solutions to process validation lifecycle challenges faced by ...
(Date:7/26/2017)... ... July 26, 2017 , ... ... has opened in Jupiter. The state of the art center will provide ... treatments with a goal of providing heart patients longer lives. , North American ...
(Date:7/26/2017)... ... July 26, 2017 , ... ... specialty pharmacies, has released an updated version of the HCV Treatment Path app ... treating chronic hepatitis C virus (HCV) infection. All of the latest HCV medications ...
(Date:7/25/2017)... ... July 25, 2017 , ... Creative Pharmacist and ... provide the Pharmacist eCare Plan to Computer-Rx pharmacies through the STRAND ... ability to develop the Pharmacist eCare Plan, a shared document detailing a patient’s ...
Breaking Medicine News(10 mins):
(Date:7/21/2017)... SPRING, Md. and RESEARCH TRIANGLE ... United Therapeutics Corporation (NASDAQ: UTHR ) announced ... financial results before the market opens on Thursday, July ... Therapeutics will host a teleconference on Thursday, July 27, ... accessible by dialing 1-877-351-5881, with international callers dialing 1-970-315-0533.  ...
(Date:7/19/2017)... 19, 2017  Mako Medical Laboratories partnered with Secretary ... Family Assistance Fund (MFA) to bring 140 soldiers back ... with their families one last time before being deployed. ... travel and logistics needed for these soldiers. "Mako Medical ... their families. We just wish we could bring them ...
(Date:7/14/2017)... July 13, 2017 It should come as no ... is in the midst of a crippling opioid epidemic. ... 1999, the number of overdose deaths from opiate-based medications has ... half a million dead from 2001 to 2015". During this ... hydrocodone has similarly quadrupled, drawing a compelling link between prescription ...
Breaking Medicine Technology: