Identification and distribution of m-tyramine in the rat.

A procedure for the quantitative evaluation of m-tyramine in mammalian tissues is described. It involves isolation of the amine by ion-exchange chromatography, followed by conversion to the dansyl derivative, chromatographic separation, and quantitation by the mass spectrometric integrated ion current technique using an isotopically labelled internal standard. The concentrations of m-tyramine in some tissues of male Wistar rats were (mean plus or minus S.D., nanograms per gram): brain 0.32 plus or minus 0.03, heart 0.44 plus or minus 0.13, kidney 12.6 plus or minus 3.4, liver 0.27 plus or minus 0.04, lung 0.33 plus or minus 0.11, spleen 0.25 plus or minus 0.07, and blood 0.15 plus or minus 0.04.