Wolff-Chaikoff effect


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Wolff-Chai·koff block

(vulf chī'kof),
obstruction of the organic binding of iodine and its incorporation into hormone, caused by large doses of iodine; usually transient, but in large doses in susceptible people, the effect can be prolonged and cause iodine myxedema.
[Louis Wolff; Israel Chaikoff]

Wolff-Chaikoff effect

[woo͡lf′ chī′kəf]
the decreased formation and release of thyroid hormone in the presence of an excess of iodine.

Wolff-Chaikoff effect

Endocrinology An acute adaptive response to high doses of iodine–↑ intracellular iodide blocks the organic-binding and coupling reactions in the thyroid, functionally turning off the thyroid; the WCE used to prepare the thyroid for surgery. See Hyperthyroidism.

Wolff,

Louis, U.S. cardiologist, 1898-1972.
Wolff-Chaikoff block - blocking of the organic binding of iodine and its incorporation into hormone caused by large doses of iodine. Synonym(s): Wolff-Chaikoff effect
Wolff-Chaikoff effect - Synonym(s): Wolff-Chaikoff block
Wolff-Parkinson-White syndrome - an electrocardiographic pattern sometimes associated with paroxysmal tachycardia. Synonym(s): preexcitation syndrome

Wolff-Chaikoff effect

increased blood levels of thyroglobulin bound iodide inhibit further binding of iodide by the thyroid gland.
References in periodicals archive ?
Keywords: Amiodarone, Thyroid disorder, Wolff-Chaikoff effect, Hypothyroidism, thyrotoxicosis.
7 During amiodarone metabolism in liver, large amount of iodide is released which initiates the Wolff-Chaikoff effect (blockage of thyroid iodide uptake and hormone synthesis as an adaptive response to high concentration of iodide to avoid hyperthyroidism).
Many thyroidologists consider an iodine intake greater than 1 to 2 mg to be potentially harmful, citing the Wolff-Chaikoff effect (39) and an increase in TSH (thyroid stimulating hormone) concentration with intakes greater than this amount.
The Wolff-Chaikoff effect, a temporary inhibition of thyroid hormone synthesis that supposedly occurs with increased iodine intake, is of no clinical significance.
This fictitious phenomenon became known as the Wolff-Chaikoff effect.
The rats used in the Wolff-Chaikoff experiment were successful in escaping the Wolff-Chaikoff effect because they received significant amounts of iodine, improving their cognition.
The demonstration of the Wolff-Chaikoff effect in man remains presumptive.
Nishiyama, et al (20) did not fail to mention the fictitious W-C effect as the cause of elevated TSH and reduced thyroxine in these 15 infants even though these infants had normal free thyroxine levels and Wolff and Chaikoff never demonstrated elevated TSH and low thyroxine in their rats, or, for that matter, in any animal species: "Because of antithyroid effects of an iodine excess, the so-called Wolff-Chaikoff effect, which blocks the uptake of iodine by the thyroid gland, leads to reduced [T.
In the next issue of this journal, this author discusses the Wolff-Chaikoff effect and presents evidence that the data reported in the rats by Wolff and Chaikoff (3) did not justify the interpretation of these data as applied to rats.
The Wolff-Chaikoff effect was not observed in some 4,000 patients on orthoiodosupplementation for as long as three years with daily intake ranging from 12.
Wolff, (5) coauthor of the world famous Wolff-Chaikoff effect published in 1948.
7)" Reference 7 of their manuscript is a study published in 1949 by Stanley (26) one year after the Wolff-Chaikoff Effect was reported in rats.