Changes of Purine Nucleotide Metabolism of Ehrlich Ascites Cells During Transition of Tumour Growth

Abstract

During the in vivo growth of Ehrlich ascites tumour there exists a proliferating phase, in which the number of cells increases quasi-exponentially, followed by a resting phase, in which the number of cells stays practically constant (Benndorf et al., 1988). The transition of growth phases is accompanied by structural deterioration and decreased number of mitochondria (Siems et al., 1989), and a multitude of metabolic changes, e. g. substrate utilization, energy production (Schmidt et al., 1991), synthesis of specific proteins (Benndorf et al., 1988) and uptake of radioactive labeled adenine, hypoxanthine and inosine (Siems et al., 1989).