Blood Amino Nitrogen in Tumour-bearing Mice

THERE is an extensive literature on the chemical abnormalities of the blood of cancerous patients and tumour-bearing animals. However, very little work on disturbances in the concentration of amino acids in the blood of tumourbearing hosts has been published. Goldfeder (1934), who studied the different fractions of non-protein nitrogen in man, observed a rise in the level of the amino acid nitrogen in the blood of cancerous patients. In most cases this increase was slight, but in a few instances of cancer of the breast his figures were about double the normal value. Malowan (1932) -also found blood changes of the same low order, though Becher and Herrmann (1932) stated that they were unable to find any significant change that could be attributed to the presence of the tumour. All the above workers used Danielson's modification of Folin's well-known colorimetric method for blood amino acids. A study, by a more specific quantitative method, of the oc-amino nitrogen in the blood of mice bearing experimentally transplanted tumours is reported in this paper.