Abstract:

MANY investigators have found1-4 that the rat, unlike the mouse, is afforded little or no protection to irradiation damage by the prior administration of cyanide salts. In all their experiments, a limited dose-range of cyanide was tested. The frequently cited results of Dowdy et al.1, for example, were obtained using a single dose (3 mg/kg) of sodium cyanide. A recent theory5 states that compounds such as cyanide and azide owe their radiobiological action to the property of stabilization of cuprous (Cu I) ion involved in oxidative processes. The proposal suggests that the dose required to achieve protection would be sharply defined and, if not limited by chemical toxicity of cyanide, it should be possible to demonstrate protection in the rat using the proper dose. Accordingly, survival was compared in rats and mice given a wide range of doses of sodium cyanide prior to X-irradiation. © 1963 Nature Publishing Group.