GLUTATHIONE METABOLISM DURING YOSHIDA ASCITES SARCOMA GROWTH

Glutathione (GSH) metabolism and protein synthesis were observed over a period of about two weeks in Yoshida ascites sarcoma and intracellul ar concentration relative to days 7, 10 and 13 assumed as 'markers' of different stages of tumor development. During this period the decreas e in rate of cell proliferation was followed by decrease in protein sy nthesis, GSH, oxidized glutathione (GSSG), adenosine triphosphate (ATP ), glutathione-S-transferase (GSH-S-transferase) and gamma-glutamyl-cy steine synthatase (gamma-GCS); by increase in glutathione-peroxidase ( GSH-peroxidase); while glutathione-reductase (GSH-reductase) and gluco se-6-phosphate-dehydrogenase (G-6-PD) remained unchanged. In relation to growth curve of the tumor, GSH concentration was very high up to da y 7 (logaritmic phase), decreased till quantity similar to that of cor responding normal cells up to day 10 (plateau phase) and on day 13 was significantly smaller. Correlation between high concentration of GSH in tumor cells and their survival and proliferation after intraperiton eal implantation is discussed.