How Nitric Oxide Maintains Health

02/18/09
Pharmacologist Louis Ignarro discusses the ‘miracle molecule’ responsible for dilation of blood cells in the human body.
By Athan Bezaitis
Dean Gerald C. Davison, left, and UCLA professor Louis Ignarro

Photo/Athan Bezaitis
Nobel Prize-winning pharmacologist Louis Ignarro visited the USC Davis School of Gerontology on Feb. 12 to discuss the health benefits of nitric oxide, which has been hailed as the “miracle molecule” because of its extraordinary importance in the health of virtually every cell in the body.

Ignrarro, professor at the UCLA Department of Molecular and Medical Pharmacology, was a co-recipient of the 1998 Nobel Prize in Medicine with Robert F. Furchgott and Ferid Murad. Together, the researchers discovered that nitric oxide, not to be confused with nitrous oxide (a gas used in anesthesia), is a signaling molecule responsible for dilation of blood vessels.

“In the heart, nitric oxide is the body’s way of protecting against cardiovascular disease,” Ignarro said. “The arteries make nitric oxide to lower blood pressure and improve blood flow to organs because it is a vaso-dialator, which means it widens or relaxes the arteries so that more blood can flow through, therefore lowering the pressure within the arterial system.”

When nitric oxide becomes deficient, Ignarro said, barriers break down and protection is lost, making people more susceptible to high blood pressure, arteriosclerosis and heart disease.

“It’s the body’s natural way of preventing strokes and heart attacks provided we make enough of it.”

To produce nitric oxide, the body uses two amino acids. The primary one is arginine, which is found in fresh vegetables, garlic, green tea, meats, grains and fish and which passes through the intestine into the blood. The other is citrulline.

“It is important therefore to maintain healthy levels of arginine at all times because when we develop certain cardiovascular and other related diseases characterized by a deficiency in nitric oxide, the main reason for the deficiency is a lack of arginine,” he said.

Ignarro also recommended at least 20 minutes of cardiovascular exercise three days a week. “Physical activity is the most important way the body makes nitric oxide,” he said. “When you exercise, the heart beats faster and stronger, increasing blood flow through the arteries, which stimulates nitric oxide production.”

For more information on the benefits of nitric oxide, Ignarro referred people to his most recent book, NO More Heart Disease: How Nitric Oxide Can Prevent Even Reverse Heart Disease and Stroke, which he said “allows him to bring the nitric oxide story to a great many people.”

Following the lecture, USC Davis School Dean Gerald C. Davison compared Ignarro’s discovery of the role of nitric oxide in health and longevity to an “intriguing detective story.”

Davison said, “It was a treat to see how an uncommonly creative and passionate researcher developed a new idea and to see also how basic science can yield unexpected positive results for the betterment of the human condition.”

Ignarro was the fourth speaker to appear at the 2008-09 Andrus Gerontology Center/AARP Distinguished Lecture Series.