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Medical Term:


Pronunciation: sit'rul-en


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 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.