Use of Neutron Activation Analysis for Studying Stable Iodine Uptake by the Thyroid

Journal Article · Wed Nov 01 04:00:00 EST 1961 · Journal of Clinical Investigation

DOI:https://doi.org/10.1172/JCI104424· OSTI ID:4832004

Wagner, Henry N.; Nelp, Wil B.; Dowling, James H.

A technique of neutron activation analysis was used to measure trace quantities of inorganic iodide in urine. Anion exchange resins and selective elution permitted removal of interfering sodium and chloride from urine prior to the activation procedure. The uptake of stable iodide by the thyroid was determined by measuring the radioiodine uptake and specific activity (I¹³¹/I¹²⁷) of simultaneously excreted urine. ln 34 fasting euthyroid subjects the mean iodide uptake by the thyroid was 3 plus or minus 2 mu g per hour. Plasma concentration of inorganic iodide averaged 0.005 mu g per ml. Day to day variations in iodide intake resulted in corresponding variations in the amount of stable iodide accumulated by the thyroid, since iodide accumulation approximated a first-order reaction. Prolonged administration of exogenous iodide resulted in a gradual decrease in radioiodine accumulation. This resulted in a decreased accumulation of stable iodide only after several weeks of greatly increased iodide uptake by the thyroid. A mechanism postulated to explain the dynamics of iodide accumulation by the thyroid is presented.

• Research Organization: Johns Hopkins Univ., Baltimore; and U.S. Naval Hospital, Bethesda, Md.
• Sponsoring Organization: USDOE
• NSA Number: NSA-16-001344
• OSTI ID: 4832004
• Journal Information: Journal of Clinical Investigation, Journal Name: Journal of Clinical Investigation Journal Issue: 11 Vol. 40; ISSN 0021-9738
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACTIVATION ANALYSIS
BIOLOGY AND MEDICINE
BLOOD PLASMA
IODIDES
IODINE 127
IODINE 131
ION EXCHANGE MATERIALS
METABOLISM
NEUTRONS
QUANTITY RATIO
RESINS
THYROID
URINE