Effect of Cortisone on Distribution of Fluorene-2,7-di- (sulfonamido-2-naphthalene)-S in Rats and Mice*

SUMMAEY The effect of cortisone (total dose--~4 rag/rat and 12 mg/mouse) on the distribution of fluorene-2,7-di(sulfonamido-2-naphthalene)-S 35 6 hours following intravenous injection of this compound into Wistar rats and CAF~/Jax mice was studied. Both sexes and species treated with cortisone showed significant reduction in the weights of thymus and spleen, except that there was no effect on the spleen weight of female rats. In the thymus of experimental male rats and male and female mice the concentration of the S3Mabeled compound was considerably increased compared with that of controis; no effect was observed on the thymus of female rats. Unlike the presence of tumor, cortisone did not affect the uptake of this derivative by the liver and spleen of rats and male mice. The only tumor-like effect of cortisone was found in the decreased concentration of the radioactivity in the liver of female mice.