EFFECT OF HYPOPHYSECTOMY ON I131METABOLISM IN NORMAL AND THIOURACIL TREATED C3H MICE

Abstract
The I131 content of the thyroid glands 25 hrs. after 1131 admn. in male C3H mice with normal or hyperplastic thyroid glands decreased progressively with increasing time after hypophysectomy. The proportion of the thyroid I131 in the thyroxine fraction also decreased rapidly after hypophysectomy in mice fed the stock diet. The thyroid iodide/serum iodide concn. ratio in the mice with hyperplastic thyroids exhibited a decrease during the 13 days after hypophysectomy but remained elevated above 50. The decreased accumulation of bound I131 in the thyroid glands of these hypophysectomized mice did not appear to be due to a decrease in thyroid radioiodide concn.