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The posterior pituitary (also called the neurohypophysis) comprises the posterior lobe of the pituitary gland and is part of the endocrine system. It consists mainly of neuronal projections (axons) extending from the supraoptic and paraventricular nuclei of the hypothalamus that secrete peptide hormones into the capillaries of the hypophyseal circulation. The neurohypophysis also contains a specialised type of astrocytic glial cell - "pituicytes".

Contents 1 Anatomy 2 Major hormones secreted 3 Role in disease 4 See also 5 References & Bibliography 6 Key texts 6.1 Books 6.2 Papers 7 Additional material 7.1 Books 7.2 Papers 8 External links

[edit] Anatomy

Despite its name, the posterior pituitary gland is not a gland, per se; rather, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary gland. It is derived embryonically from downward-growth of the diencephalon. This tissue receives its blood supply from the inferior hypophyseal artery, and secretes hormones into the hypophyseal vein. These hormones are actually made in the hypothalamus and transported to the posterior pituitary gland, where they are stored.

The posterior pituitary has three main components:

• pars nervosa
• infundibular stalk
• median eminence

[edit] Major hormones secreted

Hormones known classically as posterior pituitary hormones are synthesized by the hypothalamus. They are stored and secreted by the posterior pituitary into the bloodstream.

Hormone	Target	Effect
Oxytocin	Uterus, mammary glands	Uterine contractions; lactation
Vasopressin (antidiuretic hormone; ADH)	Kidneys or Arterioles	Stimulate water retention or raise blood pressure by contracting arterioles

[edit] Role in disease

Insufficient secretion of vasopressin is central diabetes insipidus, in which the body loses the capacity to concentrate urine. Affected individuals excrete as much as 20 L of dilute urine per day. Oversecretion of vasopressin causes the syndrome of inappropriate antidiuretic hormone.

One can readily see if the functioning of this structure is affected by psychological stress via the rest of the neuroendocrine system why mothers might have difficulty giving birth, why they might have difficulty breastfeeding or why some individuals might experience kidney or micturation problems.

[edit] See also

[edit] References & Bibliography

[edit] Key texts

[edit] Books

[edit] Papers

[edit] Additional material

[edit] Books

[edit] Papers

• Google Scholar

[edit] External links

Endocrine system - Pituitary gland - edit
Posterior pituitary: Pars nervosa | Median eminence | Infundibular stalk
Anterior pituitary: Pars intermedia | Pars tuberalis | Pars distalis | Somatotropes | Lactotropes | Thyrotropes | Gonadotropes | Corticotropes

This box: view • talk • edit Brain: diencephalon
Epithalamus	Pineal body • Habenula (Habenular nuclei)
Hypothalamus	anterior: Anterior hypothalamic nucleus • Paraventricular nucleus • Preoptic area • Supraoptic nucleus • Suprachiasmatic nucleus intermediate/middle/tuberal/pituitary: infundibulum • median eminence • arcuate nucleus • Ventromedial nucleus • Dorsomedial hypothalamic nucleus • Tuber cinereum, Pituitary gland (Anterior pituitary, Posterior pituitary) posterior/lateral: posterior nucleus • Mammillary body • Lateral nucleus other: Medial forebrain bundle
Subthalamus	Subthalamic nucleus • Zona incerta • Thalamic fasciculus • Lenticular fasciculus
Thalamus/nuclei	Ventral nuclear group (VA/VL, VP/VPM/VPL) • MD • AN • LNG (Pulvinar) • Intralaminar nucleus (Centromedian nucleus) • Midline nuclear group • Thalamic reticular nucleus • Metathalamus (MG, LG) • Interthalamic adhesion
Third ventricle	recesses: (Optic recess, Infundibular recess, Suprapineal recess, Pineal recess) • Hypothalamic sulcus
Other	Interventricular foramina • Optic chiasm • Subfornical organ • Mammillothalamic tract

This page uses content from the English-language version of Wikipedia. The original article was at Posterior pituitary. The list of authors can be seen in the page history. As with Psychology Wiki, the text of Wikipedia is available under the GNU Free Documentation License.