[The role of a decrease in pH in enhancing the antitumor action of ionizing radiation with the aid of hyperglycemia]

The role of a pH decrease in glucose-enhanced antitumor action of prior irradiation was investigated in experiments on mice with Ehrlich solid carcinoma. For this purpose changes in pH and the blood flow as well as the modification of a tumor radiation effect caused by glucose and weakly metabolizing galactose injected in similar regimens, were compared in parallel groups. It was shown that in both regimens glucose and galactose injections resulted in approximately the same reduction of a blood flow rate in tumors, however a pH decrease after the use of glucose was much greater, and glucose-enhanced antitumor radiation action was more noticeable. A conclusion has been made that a pH decrease in tumors is a major factor determining the efficacy of glucose as a radiomodifier.