Thyroid Thyroid The thyroid gland, or simply the thyroid, is an endocrine gland in the neck, consisting of two lobes connected by an . It is found at the front of the neck, below the Adam's apple. The thyroid gland secretes thyroid hormones, which primarily influence the metabolic rate and protein synthesis. The hormones also have many other effects including those on development. The thyroid hormones triiodothyronine (T) and thyroxine (T) are created from iodine and tyrosine. The thyroid also produces the hormone calcitonin, which plays a role in calcium homeostasis. Hormonal output from the thyroid is regulated by thyroid-stimulating hormone
Thyroid disease (lymphocytic infiltration) and destruction (fibrosis) of the gland. Goiter is the general enlargement of the thyroid that can be associated with many thyroid diseases. The main reason this happens is because of increased signaling to the thyroid by way of TSH receptors to try to make it produce more thyroid hormone. This causes increased vascularity and increase in size (hypertrophy) of the gland. In hypothyroid states or iodine deficiency, the body recognizes that it is not producing enough thyroid hormone and starts to produce more TSH to help stimulate the thyroid to produce more thyroid hormone. This stimulation causes the