STUDIES IN IODINE METABOLISM BY THE USE OF A NEW RADIOACTIVE ISOTOPE OF IODINE

Abstract

A recently discovered radioactive isotope of I was used in a study of I metabolism in a group of patients with goiters of various degrees of functional activity, in 2 patients with spontaneous myxedema, and in a group of normal subjects. The radioactive I was administered as a single dose in the form of a soln. of NaI containing 14 mg. of I. 24 hr. urine samples were collected for 5 successive days and the feces for this 5-day period were studied as one specimen; the thyroid glands of the patients who came to surgery were removed 2 days after the radioactive I had been given. The radioactive I content of all of these specimens was detd. quantitatively, and the total I of most of the thyroid glands was measured quantitatively. 50 to 87% of the I was excreted in the urine in 48 hrs., and 0.6 to 15.4% in the succeeding 72 hrs. In the 5 days'' samples of feces 0.06 to 11.25% was excreted. The thyroid glands contained from 0.07 to 17.5% of the radioactive I.