Effect of Estrone on Some Criteria of Thyroid Function

¹ From the Radioisotope Service, Veterans Administration Hospital, Long Beach and School of Medicine, University of California, Los Angeles, California

The effects of estrogen upon thyroidal I¹³¹ uptake, hormone discharge, total iodine content and distribution of radioiodine among the iodinated amino acids of the thyroid gland have been investigated in orchiectomized rats. Acute administration of estrone increased significantly the 24-hour I¹³¹ uptake and augmented thyroidal weight at the higher of the two levels employed. It had no effect upon the serum PBI, the I¹²⁷ content of the thyroid or the iodinated amino acid pattern. I¹³¹ discharge from the thyroid was slowed significantly by estrone, both on a stock diet and when propylthiouracil was used to block I¹³¹ reaccumulation.