The Effect of a Thyrotrophic Hormone Preparation on the Metabolism of Radioiodine in Euthyroid, Hyperthyroid and Acromegalic Individuals 1

The role played by the thyroid stimulating hormone (TSH) of the pituitary in thyroid disease has excited speculation for some time. The similarity of the effects produced by this material to some of the physiological changes noted in Graves' disease seems more than coincidental. It was early shown that the injection of a crude anterior pituitary preparation in man would cause an elevation in the basal metabolic rate (1, 2). Later studies have shown that thyrotrophin administration to euthyroid normals will increase the radioiodine uptake of the thyroid and the level of the proteinbound iodine of the serum (3-5). Goldsmith, Stanbury, and Brownell have recently demonstrated that the injection of preparations of this material causes an increase in the rate of release of hormone from the thyroid gland (6). Studies on the rat and chick have demonstrated similar changes (7-10).