The Metabolic Fate of Sulfur35 in Sheep

Abstract

Data on the tissue uptake and excretion of radiosulfur by sheep after oral administration of single and multiple doses of labeled sulfate are presented. Absorption of labeled sulfur into the blood was rapid, with the peak occurring within 6 hours. Excretion of the major part of the dose was fairly rapid, with an average of 49% excreted in the urine and 31% in the feces during the 4-day collection period. Appreciable amounts of labeled sulfur were found in all tissues analyzed. Liver, kidney, adrenals, thyroid, spleen, skin, intestinal tissues and cartilage showed greater uptake than muscle tissue. Fractionation studies revealed that most of the labeled sulfur in liver, spleen and skin was in the form of cystine and methionine. When labeled sulfate was given three times weekly over a period of 24 days the excretion pattern of the individual doses appeared to be similar to that observed for a single dose. Wool fibers contained radiosulfur in the half inch of new growth.