Thaindian News

Washington, May 5 (IANS) Exercise both reduces the risk of a heart attack and protects it from injury if a heart attack has occurred, researchers say.

For years, doctors have been trying to figure out how this second benefit of exercise works.

Researchers at Emory University School of Medicine, US, have identified the ability of the heart to produce and store nitric oxide as an important way in which exercise protects the heart from injury, reports the journal Circulation Research.

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, according to an Emory statement.

Both the chemical nitrite and nitrosothiols, where nitric oxide is attached to proteins via sulphur, 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 strengthen the case for nitrite and nitrosothiols as possible protectants from the damage of a heart attack.

“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,” said study co-author David Lefer, professor of surgery at Emory School of Medicine.

“These more stable nitric oxide intermediates appear to be critical for the cardio-protection against a subsequent heart attack,” Lefer said.