Protection of mouse chromosomes against whole-body gamma irradiation by SH-compounds

Of the several chemicals considered for radioprotection, WR-2721 (S-2-(3-aminopropylamino)phosphorothioic acid), a derivative of cysteamine, has been found to be the most effective in protecting mammals (Yuhas et al, 1980). Another synthetic compound, MPG (2-mercaptopropionylglycine), has attracted attention since Sugahara et al (1970) discovered that it protects mammals against radiation death at a very low, non-toxic dose of 20 mg/kg body weight, which is optimal for protection. Most of the studies with these compounds have taken lethality and tissue injury as the end-points and very little is known about their effects on the genetic material. Experiments were, therefore, performed to study the protective effect of WR-2721 and MPG individually on the bone-marrow chromosomes of adult mice when administered before acute whole-body exposures.