The Metabolism of Tyramine, I-tyrosine, and Phenol by Rat Tissues in Vitro

Ewins and Laidlaw (1) showed that tyramine disappeared when perfused through the heart, liver, or uterus of rabbits and cats. The amine oxidase, which deaminates tyramine and many other primary amines, has been studied in liver and kidney (2) but no further observations have been made on the fate of tyramine in the heart or other muscle. In particular it is not known whether muscle is able to deaminate the side chain of tyramine or break the nucleus or both. It was therefore of interest to investigate this question with the tissue slice technique. Tyramine, I-tyrosine, and phenol were chosen for comparison, and the changes in the amino nitrogen of the first two and the hydroxy groups of all three coinpounds were estimated after incubation with various tissue slices.