| Abstract: | Nitro--arginine (-NNA) is an inhibitor of the enzyme nitric oxide synthase (NOS). We developed a simple, sensitive and reproducible reversed-phase high-performance liquid chromatographic method for detection of nitro-arginine (- and -enantiomer) in rat plasma and urine. Samples were treated with perchloric acid, neutralized and eluted through a C8 reversed-phase column with a mobile phase of 18.5 mM heptanesulfonic acid-10% methanok in water using theophylline as an internal standard. Plasma recovery for both isomers was complete, and the sensitivity limit was 0.5 μg/ml. This method may be used for disposition studies of -NNA in small animals. |
