Studies on the metabolism of Tetrahymena pyriformis GL VII. Influence of metabolites on gamma-irradiation.

T. pyriformis, strain GL, is protected against gamma-irradiation by compounds increasing the oxygen consumption. Sodium nitrite added to ciliated before irradiation affords protection while, on the other hand, experiments with oxygen pressure reduction during irradiation did not give positive results. This failure of protection is due to the loss of oxygen debt repayment. Fluoroacetate is too toxic to reduce irradiation damage by DNase inhibition. The presence of methylene blue during irradiation results in a radiosensitizing effect.