Abstract
Chinese hamster cells were exposed to a variety of treatments after gamma-irradiation. When DNA or protein synthesis was inhibited, there was no effect on survival. There was also no effect on survival from a reduction of temperature or the addition of caffeine. Actinomycin D, acriflavine, and ethidium bromide, which have the property of binding to nucleic acids, brought about a reduction in survival. It is suggested that the activity of any enzymes which repair radiation lesions in nucleic acids is impeded in a steric manner by the resulting complexes.