Radiomimetic Substance

a chemical compound that exerts an effect on individual cells, organs, and tissues and on animals and man in general that is in many ways similar to the biological effect of ionizing radiation. Frequently, radiomi-metic substances refer to alkylating compounds, including yp-erite and ethylenimine, which have a lethal effect on the cell in all stages of the cell’s life cycle. Radiomimetic substances are similar to ionizing radiation in that they exert mutagenic and carcinogenic effects, cause acute and chronic degenerative changes in the bone marrow, intestinal mucosa, and genital organs in mammals, suppress the formation of antibodies, and impair oxidative phosphorylation and protein biosynthesis. Substances that have been isolated from irradiated organisms have an analogous effect; they are more frequently called radio-toxins. Many studies on the chemotherapy of cancer have been based on the ability of radiomimetic substances to suppress the growth of certain tumors.