THE INFLUENCE OF HYPOPHYSECTOMY UPON PLASMA IODINE AND THYROXINE CONTENT OF THE THYROID GLAND OF THE RAT1

Abstract
The level of protein-bound iodine of plasma was depressed as early as 48 hours following hypophysectomy. By the third day the concentration was reduced by 50% and no further drop occurred as late as 44 days following hypophysectomy . Normal or greater than normal amts. of thyroxine were present in the thyroid glands of hypophysectomized rats. These results indicate the importance of the thyrotrophic hormone in both the rate of formation of thyroxine and of the release of thyroxine by the thyroid gland.