Wolff –Chaikoff effect large doses of iodide act directly on the thyroid to produce a mild and transient inhibition of organic binding of iodide and hence of hormone synthesis.

TLS Online TPP Program

#Id: 5788

#Unit 7. System Physiology – Animal

Thyroid stimulating hormone induces both NIS expression and the retention of NIS in the basolateral membrane.

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#Id: 5789

#Unit 7. System Physiology – Animal

Iodide is transported out of the thyroid cells across the apical membrane into the follicle by a chloride-iodide ion counter- transporter molecule called pendrin.

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#Id: 5790

#Unit 7. System Physiology – Animal

Thyroglobulin is a glycoprotein contains 123 tyrosine residues, but only 4–8 of these are normally incorporated into thyroid hormones.

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#Id: 5791

#Unit 7. System Physiology – Animal

Oxidation of iodine is mediated by thyroid peroxidase, a membrane-bound enzyme found in the thyrocyte apical membrane.

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#Id: 5792

#Unit 7. System Physiology – Animal

When the peroxidase system is blocked or when it is hereditarily absent from the cells, the rate of formation of thyroid hormones falls to zero