A goiter is associated with which of the following hormones?
A Thyroid hormone
B Estrogen
C Oxytocin
D Epinephrine/Norepinephrine
The correct answer and explanation is:
The correct answer is A. Thyroid hormone.
A goiter is an abnormal enlargement of the thyroid gland, which is located at the base of the neck. It is typically caused by an imbalance in the levels of thyroid hormones, which are produced by the thyroid gland itself. The thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3), play a crucial role in regulating metabolism, growth, and development.
In cases of hypothyroidism (a condition where the thyroid gland is underactive and produces insufficient thyroid hormones), the body compensates by increasing the production of thyroid-stimulating hormone (TSH) from the pituitary gland. High levels of TSH stimulate the thyroid gland to grow in an attempt to produce more thyroid hormones, leading to the formation of a goiter. Conversely, hyperthyroidism (an overactive thyroid) can also cause a goiter due to the excess production of thyroid hormones.
One common cause of a goiter is iodine deficiency, as iodine is a key element needed for the production of thyroid hormones. In regions where iodine is insufficient in the diet, the thyroid gland becomes unable to produce adequate thyroid hormones, leading to an increase in TSH and subsequent goiter formation. Graves’ disease and Hashimoto’s thyroiditis are autoimmune disorders that can also lead to goiter.
In contrast, hormones like estrogen, oxytocin, and epinephrine/norepinephrine are not typically associated with goiter. Estrogen affects various reproductive and metabolic processes, oxytocin is involved in childbirth and lactation, and epinephrine/norepinephrine are stress hormones produced by the adrenal glands, none of which directly influence thyroid gland size or function.