Introduction
The thyroid gland is an essential gland found in various vertebrates, and has thyroid follicles (comprised of thyroid epithelia cells), which are supplied by a dense network of blood capillaries. The thyroid tissue’s main function is the biosynthesis and secretion of the thyroid hormone, which is an essential biological molecule existing in either of two forms, T3 and T4. The activity of the thyroid gland is controlled through the neuroendocrine system, which involves the hypothalamus and the secretory actions of the pituitary gland. TSH plays a key role in stimulating the thyroxin-binding globulin (TGB) and the uptake of blood iodine ...