ABSTRACT
In experiments with irradiated cells of Chinese hamster and Ehrlich ascites tumor a study was made of the influence of energy provision on their interphase death rate. The presence of the uncoupler of respiration and oxidative phosphorylation--carbonyl cyanide-3-chlorophenylhydrazone--in a medium without glucose was shown to drastically increase the interphase death rate of cells of both types, whereas this effect was not observed in a medium with glucose.
Subject(s)
Cell Survival/radiation effects , Energy Metabolism/radiation effects , Interphase/radiation effects , Animals , Carbonyl Cyanide m-Chlorophenyl Hydrazone/pharmacology , Cell Line , Cell Survival/drug effects , Dose-Response Relationship, Radiation , Energy Metabolism/drug effects , In Vitro Techniques , Interphase/drug effectsABSTRACT
Interphase death of in vitro irradiated (200 Gy) Ehrlich ascites tumor cells was studied as a function of oxygenation level and medium pH. The presence of oxygen both during and after irradiation as well as the increase in pH from 7.4 to 8.1 were shown to increase interphase death rate. The pronounced threshold dependence of interphase death of cells upon their concentration may be attributed to hypoxia occurring in a pericellular medium when cells concentration exceeds the threshold.
Subject(s)
Carcinoma, Ehrlich Tumor/pathology , Culture Media/pharmacology , Interphase/radiation effects , Oxygen/pharmacology , Animals , Carcinoma, Ehrlich Tumor/radiotherapy , Cell Division/drug effects , Cell Division/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Dose-Response Relationship, Drug , Gamma Rays , Hydrogen-Ion Concentration , Interphase/drug effects , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Tumor Cells, CulturedABSTRACT
A study was made of a change in the content of reduced glutathione (GSH) in Ehrlich ascites tumor (EAT) cells after irradiation with doses evoking their interphase death (ID). GSH content was determined in a suspension of EAT cells fixed by hot ethanol. The postirradiation decrease in the GSH content of the suspension was due to its oxidation by hydrogen peroxide resulting from radiochemical reactions after releasing thereof from cells upon fixation. In the absence of an irradiated medium no changes occurred in the GSH content of EAT cells. It is concluded that ID of EAT cells is not associated with the radiation-induced decrease in the content of GSH, an endogenous antioxidant.
Subject(s)
Glutathione/physiology , Interphase , Animals , Carcinoma, Ehrlich Tumor/pathology , Carcinoma, Ehrlich Tumor/radiotherapy , Cell Division/radiation effects , Cell Survival/radiation effects , Dose-Response Relationship, Radiation , Glutathione/analysis , Glutathione/radiation effects , Interphase/radiation effects , Mice , Neoplasm Transplantation , Tumor Cells, CulturedSubject(s)
Culture Media , Glucose , Radiation Tolerance , Animals , Cell Line , Hydrogen-Ion Concentration , In Vitro TechniquesSubject(s)
Culture Media , Glucose , Oxygen , Animals , Carcinoma, Ehrlich Tumor/pathology , Cell Line , Hydrogen-Ion Concentration , In Vitro Techniques , MiceABSTRACT
Changes in the intracellular pH cf Chinese hamster cells irradiated with different doses were investigated. Using the fluorescence method it was shown that irradiation of cultured cells with doses inducing reproductive death (2.5-20 Gy) caused a temporary shift of pH by 0.4-0.5 units toward the alkaline region. After a dose of 500 Gy, inducing interphase death of cells, the alkalization of the intracellular medium was more pronounced (greater than or equal to 8.0) and persisted for 1.5 h.
