Chapter 29 – Endocrine Metabolism II: Hypothalamus and Pituitary

Publisher Summary The endocrine systems of the hypothalamus and pituitary have an integrated anatomical and functional relationship. This chapter discusses the hypothalamic–pituitary regulatory system. Hypothalamic releasing hormones and release-inhibiting hormones are synthesized in various neurons. These hypothalamic hormones are transported to the anterior pituitary via a portal venous system and the anterior pituitary target cells either release or inhibit the release of specific hormones into the general circulation. The posterior pituitary hormones are synthesized and packaged in cell bodies in the hypothalamus and then are transported to nerve endings in the posterior pituitary. Afterward they are released following appropriate stimuli. The chapter discusses various hormones secreted by hypothalamous and pituitary. The hypophysiotrophic hormones are all peptides, except for dopamine that is synthesized from tyrosine. These hormones either inhibit or stimulate the synthesis and release of hormones from specific cells of the anterior pituitary. The pituitary hormones belong to three families: somatomammotropin, the glycoproteins, and opiomelanocortin.