抄録
54Mn Cl2 was added to a suspension of Ehrlich's ascitis cancer cells to a definite concentration, and the mixture together with the medium-0.9% NaCl, Tris buffer or Krebs Ringer phosphate (KRP) -was incubated in a water bath at 37°C with shaking. 54Mn was taken up by the cancer cells.
The mediums, number of the cancer cells, temperature of incubation, carriers, metabolism inhibitors, amino acids, chelating agents, metal ions and anticarionogenic agents were examined for their effects on 54Mn uptake by the cancer cells, with the following results.
1) Ehrich's ascites cancer cells gradually took up 54Mn, which was added to KRP, Tris buffer or 0. 9% NaCl. The uptake rate was relatively adrupt in the first 20 minutes, but later became slower. The uptake rate was markedly greater in KRP than in 0.9% NaCl and Tris buffer.
2) With increase in the number of the cells to 5×106, 20×106 and 60 × 106, 54Mn uptake rate was elevated. Also the uptake rate per unit number of cells was increased.
3) When KRP (pH 7.4) was used as medium, the uptake rate was highest at 37°C, and lowered with the fall of temperature.
4) Effect of carrier : The uptake was significantly decreased when 54Mn was added to a concentration of 10-3M or 10-4M.
5) Effects of metabolism inhibitors : When KRP was used as medium, the addition of MIA or DNP to 10-3M markedly decreased the uptake, while the addition of KCN conversely incerased it. The addition of DNP to 10-4M was ineffective. When Tris buffer was used as medium KCN decreased the uptake.
6) Effects of amino acids : The addition of any of glycine, L-cysteine, L-histidine or L-aspartic acid to 10-3M, significantly decreased 54Mn uptake. The addition of Na glutamate, L-lysine or L-methionine to 10-3M did not affect the uptake.
7) Effects of chelating agents : The addition of EDTA to 10-3 or 10-4M. of Na citrate, DL, D-penicillamine and ascorbic acid to 10-3M and of riboflavin to 200μg produced significant decrease of the uptake. After 100μg of tetracycline, no significant change was observed.
8) Effects of metal ions (with KRP medium) : Mn2+, Fe2+, Cu2+, Zn2+, and Fe3+ Produced increase in the 20 minute uptake. In the 60 minute value, significant increase was produced with Mg2+, Cu2+ and Fe3+, and significant decrease with Mn2+ and Ni2+.
9) Effects of anticarcinogenic agents (with KRP medium) : The addition of 100μg of Mitomycin C and of 10μg of Toyomycin significantly decreased the 20-minute uptake, and 10 and 100μg of Merphyrin, and of Nitromin significanlty decreased both the 20-minute and 60-minute values.
