Abstract
The free amino acids in brain, lung, heart, liver, muscle, kidney, spleen, blood cells, and plasma were tested for using paper chromatography on rat and cow tissues. The following were found to be present in the free form in all tissues: glycine, glutamic acid, aspartic acid,alpha-alanine, glutathione, glutamine, taurine, leucines, serine, lysine, valine, proline, threonine, tyrosine, histidine, phenylalanine, ethanolamine phosphoric acid. All except glutathione and ethanolaminephosphoric acid were present in plasma. Muscle contained in addition carnosine and methylhistidine. After oxidation a trace of methionine sulfone could be detected in many tissues. Arginine and ethanolamine were absent in all tissues. Several unknown spots were also detected.