ESTROGEN-INDUCED KIDNEY TUMORS IN THE GOLDEN HAMSTER. II. DIETHYLSTILBESTROL ABSORPTION AND DISTRIBUTION IN TISSUES.

Abstract

The effect of the degree of packing of diethylstilbestrol pellets on the rate of absorption was measured from a subcutaneous implant site as used in tumor induction studies. Three types of pellet were studied. Absorption rates varied from 150 to 630 µg diethylstilbestrol/day for the different pellet types, each type showing the highest rate of absorption during the 1st week, with a relatively constant rate from the 3d to the 8th week. Tissue distribution, after 24 hours, of an “average” daily dose (304 µg.) of C14-labeled diethylstilbestrol administered as a solution was studied and compared with absorption and tissue distribution from C14-labeled diethylstilbestrol pellets after 3 or 31 days' subcutaneous implantation. Tumor production by the three types of pellets was studied in a limited number of hamsters for a period of 6–8 months. All three types of pellet produce kidney tumors, provided the stilbestrol is continually present, the rate of absorption being an important consideration in experimental design to assure the latter requirement.