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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.

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.