The Wolff-Chaikoff Effect:

J . Wolff and I . L . Chaikoff THYROID FUNCTION HOMEOSTATIC REGULATOR OF PLASMA INORGANIC IODIDE AS A

Iodine-Induced hypothyroidism.

Iodine is an essential element for thyroid hormone synthesis. The thyroid gland has the capacity and holds the machinery to handle the iodine efficiently when the availability of iodine becomes scarce, as well as when iodine is available in excessive quantities. The latter situation is handled by the thyroid by acutely inhibiting the organification of iodine, the so-called acute Wolff-Chaikoff ...

Escape from the acute Wolff-Chaikoff effect is associated with a decrease in thyroid sodium/iodide symporter messenger ribonucleic acid and protein.

In 1948, Wolff and Chaikoff reported that organic binding of iodide in the thyroid was decreased when plasma iodide levels were elevated (acute Wolff-Chaikoff effect), and that adaptation or escape from the acute effect occurred in approximately 2 days, in the presence of continued high plasma iodide concentrations. We later demonstrated that the escape is attributable to a decrease in iodide t...

The temporary nature of the inhibitory action of excess iodine on organic iodine synthesis in the normal thyroid.

IN 1944, Morton et al. observed that when 300 mg. of sheep thyroid slices were incubated in 3 cc. of a bicarbonate-Ringer medium to which various amounts of I as inorganic iodide had been added, inhibition of thyroxine and diiodotryosine formation occurred when the added I exceeded 20 gamma. The resemblance of this in vitro effect to the action of excess iodide in Graves' disease in man led us ...

Posttranscriptional regulation of sodium-iodide symporter mRNA expression in the rat thyroid gland by acute iodide administration.

Iodide is an important regulator of thyroid activity. Its excess elicits the Wolff-Chaikoff effect, characterized by an acute suppression of thyroid hormone synthesis, which has been ascribed to serum TSH reduction or TGF-beta increase and production of iodolipids in the thyroid. These alterations take hours/days to occur, contrasting with the promptness of Wolff-Chaikoff effect. We investigate...