The Hypothalamus Coordinates the Activity of the Pituitary Gland Through the Secretion of Peptides and Amines
As indicated previously, the two major controlling systems are the nervous and the endocrine systems. The interface between these systems occurs, for the most part, in the hypothalamus.
The hypothalamus is an area of the diencephalon that forms the floor of the third ventricle and includes the optic chiasma, tuber cinereum, mammillary bodies, and the median eminence. Often not included in this classification are the infundibulum and the neurohypophysis (stalk of the posterior lobe and the posterior lobe, respectively), although both tissues represent extensions of the hypothalamus into the pituitary gland.id="Picutre 330" class="lazyload" data-src="/files/uch_group31/uch_pgroup304/uch_uch7229/image/image327.jpg">
FIGURE 33-10 Diagrams showing progressive stages in the embryonic development of the pituitary gland. Rathke's pouch becomes detached from the oral epithelium at stage C. (FromViIIee CAzWaIkerWF Jrr Smith FE: General zoology, ed 2r Philadelphia, 1963, Saunders, and from Turner CD, Bagnara JT: General endocrinology, ed 6, Philadelphia, 1977, Saunders.)
The hypothalamus produces peptides and amines that influence the pituitary gland to produce (1) tropic hormones (e.g., corticotropin), which in turn influence the production of hormones (e.g., cortisol) by peripheral target endocrine tissues, or (2) hormones that directly cause a biological effect in tissues (e.g., PRE). The hypothalamus is also the center for the control of a large number of autonomic nervous system control pathways.