Send to

Choose Destination
Cell Mol Life Sci. 1999 Jul;55(8-9):1015-28.

Nitric oxide biosynthesis, nitric oxide synthase inhibitors and arginase competition for L-arginine utilization.

Author information

Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, Paris, France.


Nitric oxide (NO) is a recently discovered mediator produced by mammalian cells. It plays a key role in neurotransmission, control of blood pressure, and cellular defense mechanisms. Nitric oxide synthases (NOSs) catalyze the oxidation of L-arginine to NO and L-citrulline. NOSs are unique enzymes in that they possess on the same polypeptidic chain a reductase domain and an oxygenase domain closely related to cytochrome P450s. NO and superoxide formation as well as NOS stability are finely regulated by Ca2+/calmodulin interactions, by the cofactor tetrahydrobiopterin, and by substrate availability. Strong interactions between the L-arginine-metabolizing enzymes are clearly demonstrated by competition between NOSs and arginases for L-arginine utilization, and by potent inhibition of arginase activity by N(omega)-hydroxy-L-arginine, an intermediate in the L-arginine to NO pathway.

[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center