If your thyroid gland was removed, how would it affect your pituitary gland?
1 Answer
The pituitary doesn't receive negative feedback and will continue producing thyroid stimulating hormones.
Explanation:
The production of hormones is strictly regulated in the body in a very ingenious way (see image). The pituitary produces thyroid stimulating hormone (TSH) which stimulates the thyroid gland to produce the hormones triiodothyronine (T3) and thyroxine (T4).
An increase in the levels of T3 and T4 inhibits the production of TSH by the pituitary, this is called feedback inhibition or negative feedback. This way the thyroid hormones are produced in sufficient amounts only when necessary.
When the thyroid would be taken away completely, there would be no feedback inhibition. The pituitary will continuously produce TSH to stimulate the thyroid gland (which is not there anymore).
Therefore, when the thyroid doesn't function anymore or is taken out because of disease, suppletion of thyroid hormones is essential. Of course also because the thyroid hormones serve very important functions in the body.
