The Radioprotective Action of Dimethyl Sulphoxide and Various Other Sulphoxides

SummaryA number of sulphoxides and derivatives of dimethyl sulphoxide have been tested for radioprotective action against a lethal dose of x-rays in mice. Of the sulphoxides tested, only dimethyl sulphoxide showed appreciable protective activity, in that it conferred a 70 per cent protection against a lethal dose of x-rays. The dose-reduction factor for dimethyl sulphoxide was found to be 1·33, as compared with 1·45 for A.E.T. Of the other sulphoxides tested, only five possessed weak protective activity. These were: methyl ethyl sulphoxide, tetramethylene sulphoxide, dl-methionine sulphoxide, di-phenyl sulphoxide and bis-tribromomethyl sulphoxide. It seems unlikely that either dimethyl sulphide or dimethyl sulphone is involved in the mechanism of dimethyl sulphoxide protection.