IODIDE ORGANIFICATION DEFECT IN A COLD THYROID NODULE: ABSENCE OF IODIDE EFFECT ON CYCLIC AMP ACCUMULATION

Abstract
A follicular adenoma of the thyroid was hot 1 h after 99mTc pertechnetate administration, but cold 24 h after 131I iodide administration. Incubation of the tissue in vitro demonstrated a defect in iodide binding to proteins that was abolished by addition of an H2O2 generating system. In this tissue iodide failed to inhibit TSH-induced cAMP accumulation. Iodide oxidation is required for its inhibitory action on cAMP accumulation in human thyroid.
Keywords