L-Citrulline / Citrulline is an amino acid that supports the body in optimizing blood flow through its conversion to L-arginine and then nitric oxide. Nitric oxide is involved in vasodilatation, and low levels are associated with mental and physical fatigue and sexual dysfunction.Citrulline, which is considered a non-essential amino acid synthesized in the intestinal tract from Glutamine, converts to Arginine in the endothelial cells. This biochemical process involves L-Aspartate and the enzymes Argininosuccinate Synthetase and Argininosuccinate Lyase, in the presence of ATP. Arginine is important for Nitric Oxide production for cardiovascular health; however, most Arginine is utilized in the liver and kidneys, and only a fraction is available for this purpose. Since Citrulline is a precursor to Arginine, it allows for increased and sustained Nitric Oxide production in the endothelium for support of circulatory function.
Oral Citrulline supplementation provides a readily available source of Citrulline for this purpose, and some recent research further indicates that Citrulline may be the preferred source of cellular Arginine. In addition Citrulline also increases energy, stimulates the immune system, and is essential for Urea Cycle function as well.
