Plasma catecholamines: laboratory aspects

In this review the methods used for analysis of plasma catecholamines in clinical chemical laboratories are discussed. The physiology of catecholamines as well as their measuring indications are discussed, together with concise evaluation of the methods most commonly used, namely indirect radioenzymatic assays or direct determinations by high-performance liquid chromatography combined with either electrochemical or fluorometric detection. The main advantage of radioenzymatic assay is its sensitivity and thus the need for only a small sample. Liquid chromatographic methods in general are less tedious, relatively rapid, and cheap, and omit the use of radionuclides. Both of these methods, however, are subject to a number of analytical errors, which can only be avoided by proper development of methods and skilled use of these methods. Little routine work is done using either radioimmunoassay or gas-chromatography.