FREE AMINO ACIDS IN ANIMAL TISSUE 325 
in both the cells and fluid of the 24h sample, no changes were observed in the distri- 
bution of the amino acids normally found in the tumor cells. Cytological observations 
made during the first 4h after the injection of the diaminobutyrate showed there 
to be a marked diminution in a number of mitotic cells and some chromosomal 
abnormalities characterized by the presence of clumping of chromosomes. The in- 
tense swelling accompanying uptake of the diaminobutyrate 7m vitro?” was not 
evident in our 7m vivo study. This possibly may be attributable to the different 
degrees of protection against the swelling afforded by the protein-rich ascitic fluid 
and the buffer medium employed in the 7 vitro studies. It is probably allowable to 
assume that intracellular ionic changes took place in our experiments which were 
similar to those observed 7n vitro. 
Thus, in addition to withstanding the effects of cytotoxic agents which affect all 
microscopically observable cellular structures (previous section), the mechanisms 
which control intracellular amino acid concentrations are also able to adapt to the 
uptake of large amounts of a neutral substance which is metabolized rapidly (gluta- 
mine) or of a basic substance which produces alterations in intracellular ionic and 
water balance (a, y-diaminobutyrate). 
Amino acid changes in tissues during induced growth or atrophy 
Liver at various times after partial hepatectomy. The reader is referred to recent 
reviews on liver regeneration for details of the sequential changes in many variables 
that have been studied. 39, The examination of the free amino acids of regenerating 
liver at various times after partial hepatectomy gave an opportunity to study these 
constituents in a tissue exhibiting a high rate of growth. It was found that for 20 h 
after partial hepatectomy the total amino acid content of picric acid filtrates of 
liver did not exceed those found in animals which had been subjected to laparotomy”. 
Between 20 and 30h there was a general rise in amino acids, which persisted for 
16 days. Also a fall in glutamine content and an increase in glutathione content 
were observed. In a more recent study determinations were made by photometric 
estimation of quantities of the amino acids on two-dimensional paper chromatog- 
rams of the amino acid patterns of plasma and of liver of control and partially hepa- 
tectomized rats at 6 and 24h after surgery*!. No significant changes in total free 
amino nitrogen or in individual free amino acids were found in whole blood or 
plasma. In both the 6 and 24h liver samples there were reported to be marked in- 
creases in content of aspartic and glutamic acids, lysine and ethanolamine phos- 
phate and decreases in glutamic acid and taurine by comparison with unoperated 
controls. Glutathione also was higher in the 24h sample of liver in the hepatecto- 
mized animal than in the control. The concentrations of a number of other con- 
stituents were not affected by the procedure. 
Measurements similar to those above were also performed in our laboratories” 
Figs. 217-230. Amino acids of Ehrlich ascites tumor cells (odd numbers 217-229) and ascitic 
fluid (even numbers 218—230) before and at various time after injection of a, y-diaminobutyric 
acid. Figs. 217, 218: control sample. Figs. 219, 220: 5 min. Figs. 221, 222: 10 min. Figs. 223, 224: 
20 min. Figs. 225, 226: 1h. Figs. 227, 228: 2h. Figs. 229, 230: 24h. Taurine, 5; glutamine, 13 
glutamic acid, 17; a, y-diaminobutyric acid, 25. 
References p. 348/349 
