iodoglobulin

1. A protein that contains precursors of thyroid hormone usually stored in the colloid within the thyroid follicles; biosynthesis of thyroid hormone entails iodination of the l-tyrosyl moieties of this protein and the combination of two iodotyrosines to form thyroxine, the fully iodinated thyronine; secretion of thyroid hormone requires proteolytic degradation of thyroglobulin, with the attendant release of free hormone; a defect in thyroglobulin metabolism will lead to hypothyroidism. Synonym(s): iodoglobulin, thyroprotein (1)

2. A substance obtained by the fractionation of thyroid glands from the hog, Sus scrofa, containing not less than 0.7% of total iodine; used as a thyroid hormone in the treatment of hypothyroidism.