The Radioprotective Action of Guanylthiourea and Related Compounds

Summary

Compounds incorporating the thioureido and guanidino structures have been tested for protective action against 900 r whole-body x-radiation in mice. Guanylthiourea (toluene-p-sulphonate) gave 66 per cent survival at 30 days. The more toxic oxidation product, 3,5-diamino-1,2,4-thiadiazole was four times more effective on a molar basis and gave 69 per cent survival. Substituted derivatives and analogues were less protective. Autopsies and histological studies demonstrated little reduction of intestinal causes of death but considerable protection of the bone-marrow. It seems likely that these compounds have a similar mode of action to AET and cysteamine.