抄録
In order to understand the further mechanisms of lethal actions of thermal neutrons, the combined effects of thermal neutrons and several chemical agents which interact with DNA, mainly bleomycin and actinomycin D, have been studied. Marked sensitization was observed with bleomycin even in its lower concentration, while in the case of actinomycin D, slight or no sensitization was found in its lower concentration, though considerable sensitization was observed in its high concentration (100 μg/ml). The sensitizing effects were stronger when the drug was administered before the irradiation than the case when the sequence was reversed. The marked sensitization found in the high dose of actinomycin D is considered to be the consequence of the single strand breaks in DNA chain, just as in the case of sensitization due to bleomycin.
