[On the simultaneous effects of ionising radiation and chemical agents on animal cells. 1st communication. Cytogenetic studies on X-rays and isonicotinic acid hydrazide in the Chinese hamster, Cricetulus griseus (author's transl)].

In bone marrow cells of Chinese hamsters enhanced chromosome damage is observed after 48 h treatment of the animals with isoniazid (INH) combined with X-rays only at much higher doses than normally applied in human therapy. Compared to X-ray-induced aberration levels, 125 mg/kg INH and 50 R given simultaneously increase the number of gaps and breaks, the latter being increased over-additively. This points to an interaction between both agents. The combined treatment changes the mitotic rate of the bone marrow as well.