World Library  
Flag as Inappropriate
Email this Article

Arcuate nucleus

Article Id: WHEBN0000760165
Reproduction Date:

Title: Arcuate nucleus  
Author: World Heritage Encyclopedia
Language: English
Subject: Hypothalamus, Leptin, Endocrine system, Paraventricular nucleus of hypothalamus, Opioid
Collection: Hypothalamus, Neuroendocrinology
Publisher: World Heritage Encyclopedia

Arcuate nucleus

Arcuate nucleus
Arcuate nucleus is 'AR', at bottom center, in green.
Latin nucleus arcuatus hypothalami
Part of Hypothalamus
MeSH A08.186.211.730.385.357.352.081
NeuroNames hier-378
NeuroLex ID Arcuate nucleus of hypothalamus
Anatomical terms of neuroanatomy

The arcuate nucleus (or infundibular nucleus[1]) is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. The arcuate nucleus includes several important populations of neurons, including: neuroendocrine neurons, centrally projecting neurons, and others.


  • Neuroendocrine neurons 1
  • Centrally-projecting neurons 2
  • Other 3
  • Footnotes 4
  • References 5

Neuroendocrine neurons

  • Neuroendocrine neurons with nerve endings in the median eminence release dopamine into the hypophysial portal blood. These are sometimes called the "tuberoinfundibular dopamine" (TIDA) neurons. In lactating females, TIDA neurons are inhibited by the stimulus of suckling. Dopamine released from their nerve endings at the median eminence is transported to the anterior pituitary gland, where it regulates the secretion of prolactin; dopamine inhibits prolactin secretion, so when the TIDA neurons are inhibited, there is increased secretion of prolactin, which stimulates lactogenesis (milk production). Prolactin acts in a short-loop negative feedback manner to decrease its levels by stimulating the release of dopamine. Dopaminergic neurons of the arcuate also inhibit the release of gonadotropin-releasing hormone, explaining in part why lactating (or otherwise hyperprolactinemic) women experience oligomenorrhea or amenorrhea (infrequency or absence of menses).
  • Neuroendocrine neurons, mainly in the ventrolateral part of the nucleus, make growth hormone-releasing hormone (GHRH). Like the TIDA neurons, these neurons have nerve endings in the median eminence. GHRH released into the hypophysial portal blood is transported to the anterior pituitary gland, where it regulates the secretion of growth hormone; GHRH stimulates growth hormone secretion. These neurons are inhibited by somatostatin. The reciprocal relationship between the electrical activity of GHRH neurons and somatostatin neurons leads to pulsatile secretion of growth hormone, a pattern of secretion that is important for its biological effectiveness.

Centrally-projecting neurons

  • Centrally projecting neurons that contain peptide products of pro-opiomelanocortin (POMC), and cocaine- and amphetamine-regulated transcript (CART). These neurons have widespread projections to many brain areas, including to all nuclei in the hypothalamus. These cells are important in the regulation of appetite, and, when activated, they inhibit feeding. These neurons are activated by circulating concentrations of leptin and insulin, and they are directly innervated and inhibited by the NPY neurons.[2] POMC neurons that project to the medial preoptic nucleus are also involved in the regulation of sexual behavior in both males and females. The expression of POMC is regulated by gonadal steroids. The release of a POMC product, beta-endorphin is regulated by NPY.
  • Centrally projecting neurons that make somatostatin; the neurosecretory somatostatin neurons that regulate growth hormone secretion are a different population, located in the periventricular nucleus.


  • A small population of neurons that synthesise ghrelin. The role of this population is not known; many neurons in the arcuate nucleus express receptors for ghrelin, but these are thought to respond mainly to blood-borne ghrelin.

The arcuate nucleus also contains a population of specialized ependymal cells, called tanycytes.


  1. ^ - Project: Does activation of neurons in the infundibular nucleus in menopause prevent the occurrence of Alzheimer changes?
  2. ^ Arora and Anubhuti. Role of neuropeptides in appetite regulation and obesity--a review. Neuropeptides (2006) vol. 40 (6) pp. 375-401


  • Kawano H, Daikoku S (1988). "Somatostatin-containing neuron systems in the rat hypothalamus: retrograde tracing and immunohistochemical studies". J. Comp. Neurol. 271 (2): 293–9.  
  • Cone RD (2005). "Anatomy and regulation of the central melanocortin system" (PDF). Nature Neuroscience 8 (5): 571–8.  
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.