Anatomy and Physiology of the Thyroid Gland

  • Nikolaos StathatosEmail author


The thyroid gland and its main product, thyroid hormone, play a very important role in human physiology. As such, detailed knowledge of thyroid gland embryology, anatomy, and physiology is critical for any physician managing patients with thyroid disorders. The thyroid gland is shield-shaped organ located anteriorly to the trachea in the lower neck. A variety of conditions ranging from variations or errors in the development and migration of the gland during organogenesis to mutations that lead to thyroid dysfunction can have profound effects on the human homeostasis. New insides, such as thyroid cell clonality provide potentially important clues to thyroid carcinogenesis. Any surgeon performing thyroid surgery needs to have intimate knowledge of the anatomy of the thyroid gland and its surrounding structures as well as the large numbers of variations they might encounter. Thyroid hormone plays an important role in the function of practically all human organs and tissues. Its function is under an elaborate regulation the complexity of which we understand only partially. The hypothalamic-pituitary-thyroid axis provides the classical endocrine negative feedback regulation, although there is clear evidence today that each tissue may have its own unique regulatory system as well.

The molecular biology of thyroid function is being studied in great detail. Clinically important molecules, like the thyroid-stimulating hormone receptor and the sodium iodide symporter, have been identified and well characterized. Such discoveries have significantly improved our understanding of thyroid physiology. As a result, new diagnostic and therapeutic approaches for the management of thyroid disorders are now available or in development.


Thyroid anatomy and physiology Thyroid hormone Hypothalamic-pituitary-thyroid axis Thyroid receptors Deiodinase 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Harvard Medical School, Massachusetts General HospitalBostonUSA

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