The measurement of nitric oxide metabolites may be useful for better understanding of different physiopathological processes. Thus, the aim of this study was to evaluate the influence of different anticoagulants (EDTA, citrate and heparin) and four-month storage at -20ºC on nitrite levels. The serum and plasma samples were analyzed by using the Griess method. The type of sample (serum or plasma) or anticoagulant used in the collection did not influence on nitrite levels significantly, regardless the fact they were fresh or four-month samples stored at -20ºC.
Nitric oxide; Nitrite; Griess reagent; Stability; Anticoagulants; Storage