Distribution of 35S in mice after oral administration of alpha-dithioacetamidinium chloride. An autoradiographic investigation.

The distribution of 35S in mice has been investigated by whole-body autoradiography after oral administration of the 35S labelled S-75 (2,2'-Dithiobis(N-[(1-adamantyl)-methyl]-acetamidine)dihydrochloride). The substance was rapidly absorbed, and the highest concentration occurred in the liver and kidneys. During the highest radiation protective activity (after about 45 min) a substantial concentration was found in the red pulp of the spleen. This supports previous findings that S-75 has its most marked protective effect on the splenic haemopoiesis. Previously, it was shown that cysteamine is more evenly distributed in the body than S-75, which is in agreement with its more generalized protective effect than S-75.