Mode of Action of Agents giving Protection from Radiation

Abstract

A CONSIDERABLE number of compounds is now known to be capable of protecting animals against X-rays and other radiations. Among the most effective of these are sodium cyanide and sodium azide¹, and thiourea²; alcohols³ and amines⁴ are active at higher concentrations. X-rays degrade polymethacrylic acid in aerated aqueous solutions, and the extent of the reaction could readily be followed by changes in viscosity with a high molecular weight sample of the polymer⁵. Table 1 shows that the degradation is reduced in the presence of substances which are protective agents in biological experiments. Since the compounds were placed in the same order of effectiveness in both tests, it is suggested that similar chemical reactions are involved. Allyl thiourea, which does not appear to have been examined biologically, was found in our work to be a highly effective protective agent.