On the Mechanism of the Radioprotective Action of Cyanide

Summary The mechanism of the radioprotective action of cyanide has been investigated with rat-thymocyte suspensions, cultured human-kidney cells and with mice. Cyanide does not protect cells in vitro. In the thymocyte system, cyanide has instead a slight radiosensitizing action. The presence of cyanide after the irradiation causes an inhibition of the development of eosin permeability. In mice, cyanide produces a hypoxia of the spleen and bone-marrow. This hypoxia explains the protection against a lethal dose of x-rays.