Determination of Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma and Other Biological Samples by High-Performance Liquid Chromatography

摘要: Abstract Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), may be related to reduced biosynthesis in diseases associated with accelerated atherosclerosis. The closely compound symmetric (SDMA) does not inhibit NOS, but compete arginine for cellular uptake, thereby limiting substrate availability NOS. We report on a method the simultaneous measurement arginine, ADMA, and SDMA as tool gain insight role these compounds regulation NOS activity. Sample cleanup was performed by solid-phase extraction polymeric cation-exchange columns using monomethylarginine internal standard. After derivatization ortho-phthaldialdehyde reagent containing 3-mercaptopropionic acid, analytes were separated isocratic reversed-phase HPLC fluorescence detection. stable derivatives near baseline resolution. Using sample volume 0.2 ml, linear calibration curves obtained limits quantification 0.08 μM 0.01 ADMA SDMA. Analytical recovery 98–102%, interassay CV better than 3%. Plasma from healthy volunteers (n = 53) contained 94 ± 26 0.42 0.06 0.47 Due its high precision sensitivity this is valuable research metabolism dimethylated arginines their