Metabolism of synthetic estrogens; urinary sulfur partitioning after estrogen administration.

SUMMARY 1. Urinary excretion of inorganic, ethereal, and neutral sulfur has been determined before and after administration of synthetic estrogens to rats, rabbits, cats, and dogs. 2. A rise in the ethereal sulfate fraction was sometimes found after diethylstilbestrol in rats, cats, and dogs, but not in rabbits. No increase was obtained with dienestrol in rats or with monomestrol in one rabbit. 3. The neutral sulfur fraction was usually decreased following estrogen administration. Inorganic sulfur usually fell markedly. 4. These results were interpreted to indicate that conjugation of diethyl- stilbestrol with sulfuric acid may take place in rats, cats, and dogs, The conjugation is variable in degree and at best involves only a small per- centage of the dose. It fails to occur in rabbits. It also probably fails to occur with dienestrol in rats and with monomestrol in rabbits. Prob- ably no mercapturic acid derivatives of any of the three estrogens are formed in the species studied. Changes in inorganic sulfate excretion are due to variation in food intake. It is a pleasure to acknowledge the advice and encouragement of Dr. Ralph G. Smith of Tulane University.