Paper chromatographic assay of ( 3 H)norepinephrine and its five major metabolites

The technique described here offers several advantages over the currently available assays for [³H]norepinephrine and its metabolites. The technique is simpler and has fewer sources of potential error than most currently available techniques. It provides a complete separation of norepinephrine from its five major metabolites with virtually no cross-contamination between the fractions. It is unnecessary to correct for recovery, elution from the chromatograms, or efficiency of counting the chromatogram segments. Experiments reported here demonstrate that all five major metabolites of norepinephrine are formed by rabbit aorta. Most of the neutral metabolites and normetanephrine are found in the Krebs solution used for incubating the tissue, whereas most of the acid metabolites are found in the tissue.