IODINE COMPOUNDS IN THE BLOOD AND URINE OF MAN*†§

Abstract

THE nature of the circulating organic iodine compounds in normal and hyperthyroid man has not been determined with certainty despite many investigations utilizing chemical procedures for the determination of iodine. The same situation pertains to the nature of the iodine compounds which may occur in the urine, although fewer investigations have been made on urine than on blood. Certain investigators, such as Trevorrow (1), Elmer and associates (2, 3), and Wilmanns (4), have presented evidence that free thyroxine is present in the circulating blood in an amount sufficient to account for an appreciable portion of the blood iodine. Recently Taurog and Chaikoff (5), on the basis of butanol solubility, recrystallization and solvent distribution studies, concluded that thyroxine was present in circulating blood in the form of a loosely bound protein complex and that the thyroxine accounted for about 90 per cent of the organic iodine in blood serum. Opposed to this opinion is the work of Salter and Johnston (6), who found that thyroxine added to blood serum did not behave in the same way as did naturally occurring organic iodine in serum.