L-Arginine supplementation improves endurance and quality of life in heart transplant patients

     Researchers from the Medicine Faculty Physiology Institute in Strasbourg, France tested the effects of the amino acid L-Arginine on heart transplant recipients. This is because the transplant patients have poor endurance due too poor blood flow and exercise capacity decreases after transplant. The poor blood flow is caused, at least in part, by dysfunction of the cells lining blood vessel walls. These cells known as endothelial cells have to respond to a need for increased blood flow to supply oxygen to functioning muscles, and they must expand the diameter of blood vessels to increase the flow of blood. L-Arginine works by stimulating the release of a gas known as nitric oxide. Nitric oxide is a neurotransmitter that restores the function of the endothelial cells opening up blood vessels, therefore improving blood flow.

    Eleven healthy patients and 22 heart transplant patients were supplemented with L-Arginine for 6 weeks. Some of the subjects were given inactive placebo for comparisons sake.

    Placebo had no effect. Six-weeks of L-Arginine improved the quality of life of the heart transplant patients. They could exercise moiré and walk further and breath easier. The study is published in the May 2010 issue of the American Journal of Clinical Nutrition.