The mechanism of glycolysis inhibition by x-rays in ascites-tumor cells. I. Alteration in steady-state concentrations of some intermediate nucleotides and in electrolyte equilibrium under various conditions of incubation.

Abstract

SummaryThe anaerobic glycolysis of Ehrlich ascites-tumour cells is inhibited in vitro by x-rays. For lower doses (25 kr) this inhibition is reversible, and an increase of triose and hexose phosphates has been found. With increasing dose (over 50 kr) the resulting inhibition becomes more irreversible, and the triose and hexose phosphate concentrations fall far below the normal values. In all cases, we observed a dose-dependent decrease in ATP and DPN with a slightly S-shaped dose-effect curve, as well as an increase in the potassium-diffusion. The effect of irradiation on the alteration of transport equilibria, and the corresponding decrease of QN2LA values, can be greatly reduced if metabolism is increased by adding inorganic phosphate, ATP and ADP. However, the relative alterations in triose and hexose phosphates, ATP and DPN concentrations caused by x-irradiation, remain largely unchanged by this increase. With increasing x-ray doses, phosphate-splitting enzymes are activated. A large part of DPN is alr...