Methylarginine Explained

N-Methylarginine is an inhibitor of nitric oxide synthase.^{[1] [2]} Chemically, it is a methyl derivative of the amino acid arginine. It is used as a biochemical tool in the study of physiological role of nitric oxide.

The inhibiting effect of N-methylarginine on vasodilation is lower in hypertensive patients than in normal subjects, indicating endothelial dysfunction.^[3] The inhibiting effect of N-methylarginine on vasodilation declines progressively with age, but has been restored with vitamin C in the oldest subjects.

See also

• Asymmetric dimethylarginine

Notes and References

1. Toutouzas, K. . Riga, M. . Stefanadi, E. . Stefanadis, C. . Asymmetric dimethylarginine (ADMA) and other endogenous nitric oxide synthase (NOS) inhibitors as an important cause of vascular insulin resistance . Hormone and Metabolic Research . 2008 . 40 . 9 . 655–659 . 10.1055/s-0028-1083814 . 18792879. 260167230 .
2. Stefanovic-Racic M, Meyers K, Meschter C, Coffey JW, Hoffman RA, Evans CH . N-monomethyl arginine, an inhibitor of nitric oxide synthase, suppresses the development of adjuvant arthritis in rats . . 37 . 7 . 1994 . 1062–1069 . 7517676. 10.1002/art.1780370712 .
3. Taddei S, Virdis A, Ghiadoni L, Salvetti G, Bernini G, Magagna A, Salvetti A . Age-related reduction of NO availability and oxidative stress in human . . 38 . 2 . 2012 . 274–279 . 11509489 . Up to the age of 60 years, despite the evident decline in endothelium-dependent vasodilation, vitamin C did not modify the response to acetylcholine. In contrast, in the oldest individuals (age >60 years) characterized by a profound alteration in NO availability, vitamin C not only enhanced the response to the endothelial agonist but also restored the inhibiting effect of L-NMMA on vasodilation to acetylcholine.. 10.1161/01.hyp.38.2.274 . free . 10.1.1.576.255 .