Skip to Content
Medical Term:


Pronunciation: sit'rul-en

Definition: An amino acid formed from l-ornithine in the course of the urea cycle as well as a product in nitric oxide biosynthesis; also found in watermelon (Citrullus vulgaris) and in casein. Elevated in individuals with a deficiency of argininosuccinate synthetase or argininosuccinate lyase.

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.