Periventricular nucleus

Not to be confused with Paraventricular nucleus.
Periventricular nucleus
Details
Identifiers
Latin nucleus periventricularis
TA A14.1.08.924
FMA 84354

Anatomical terminology

The periventricular nucleus is a thin sheet of small neurons located in the wall of the third ventricle, a composite structure of the hypothalamus. It functions in analgesia.

It is located in the rostral, intermediate, and caudal regions of the hypothalamus. The rostral region aids in the production of both somatostatin and thyroid releasing hormone. The intermediate portion aids in production of thyroid releasing hormone, somatostatin, leptin, gastrin, and neuropeptide y. In humans and primates it also produces GnRH. Lastly the caudal region aids in sympathetic nervous system regulation, and is regarded as the rage center. The periventricular nucleus does not have an effective blood–brain barrier.[1]

11β-HSD2 expression turns cortisol into cortisone.[2]

Role in LH & GnRH release

This nucleus has been shown to affect the release of GnRH(Gonadotropin-Releasing Hormone) in several ways. One way is its expression of neuropeptide Y, which has an impact on the hypothalamic pathway responsible for GnRH secretion.[3] The periventricular nucleus has also been shown to have many neurons that express kisspeptin, which generates a surge in LH, which ultimately leads to the release of GnRH.[4] In female rats, there is a greater expression of estrogen receptor beta in the periventricular nuclear cells, which is thought to lead to different levels of LH secretion in males and females.[5]

Role in GH release

This region has been shown to aid in the production of Somatostatin and research shows that neurons releasing somatostatin are stimulated to do so by gluatamergic innervation and then this allows them to stimulate the release of growth hormone.[6] There is thought to be a differential level of secretion of somatostatin between males and females by the periventricular nucleus and that is thought to be responsible for the sexual dimorphism of growth hormone secretion.[7] It has also been suggested that leptin secretion also plays a role in the release of GH from periventricular nucleus and that this hormone interacts with both somatostain and Growth Hormore Releasing Hormone (GHRH) in the GH release pathway.[8] This is further supported by the presence of leptin receptors in neurons of the periventricular nucleus.[9] GH may also be able to provide regulatory feedback on the periventricular nucleus by increasing cytochine signaling to the hypothalamus which inhibits the GH release pathway.[10]

References

  1. ↑ Ueno M, Akiguchi I, Hosokawa M, Kotani H, Kanenishi K, Sakamoto H (2000). "Blood-brain barrier permeability in the periventricular areas of the normal mouse brain". Acta Neuropathologica. 99 (4): 385–92. doi:10.1007/s004010051140. PMID 10787037.
  2. ↑ Seckl JR (1997). "11β-Hydroxysteroid Dehydrogenase in the Brain: A Novel Regulator of Glucocorticoid Action?". Frontiers in Neuroendocrinology. 18 (1): 49–99. doi:10.1006/frne.1996.0143. PMID 9000459.
  3. ↑ Chiba, A. (2005-07-01). "Neuropeptide Y-immunoreactive (NPY-ir) structures in the brain of the gar Lepisosteus oculatus (Lepisosteiformes, Osteichthyes) with special regard to their anatomical relations to gonadotropin-releasing hormone (GnRH)-ir structures in the hypothalamus and the terminal nerve". General and Comparative Endocrinology. 142 (3): 336–346. doi:10.1016/j.ygcen.2005.02.010.
  4. ↑ Rudolph, L. M.; Bentley, G. E.; Calandra, R. S.; Paredes, A. H.; Tesone, M.; Wu, T. J.; Micevych, P. E. (2016-07-01). "Peripheral and Central Mechanisms Involved in the Hormonal Control of Male and Female Reproduction". Journal of Neuroendocrinology. 28 (7): n/a–n/a. doi:10.1111/jne.12405. ISSN 1365-2826.
  5. ↑ Orikasa, Chitose; Kondo, Yasuhiko; Hayashi, Shinji; McEwen, Bruce S.; Sakuma, Yasuo (2002-03-05). "Sexually dimorphic expression of estrogen receptor β in the anteroventral periventricular nucleus of the rat preoptic area: Implication in luteinizing hormone surge". Proceedings of the National Academy of Sciences. 99 (5): 3306–3311. doi:10.1073/pnas.052707299. ISSN 0027-8424.
  6. ↑ Kiss, József; Csaba, Zsolt; Csáki, Ágnes; Halász, Béla (2006-10-16). "Glutamatergic innervation of growth hormone-releasing hormone-containing neurons in the hypothalamic arcuate nucleus and somatostatin-containing neurons in the anterior periventricular nucleus of the rat". Brain Research Bulletin. 70 (4–6): 278–288. doi:10.1016/j.brainresbull.2006.05.006.
  7. ↑ Murray; Simonian. "Correlation of hypothalamic somatostatin mRNA expression and peptide content with secretion: sexual dimorphism and differential regulation by gonadal factors". Neuroendocrinology.
  8. ↑ Carro, E.; Señarís, R. M.; Seoane, L. M.; Frohman, L. A.; Arimura, A.; Casanueva, F. F.; Diéguez, C. (1999-01-01). "Role of growth hormone (GH)-releasing hormone and somatostatin on leptin-induced GH secretion". Neuroendocrinology. 69 (1): 3–10. doi:10.1159/000054397. ISSN 0028-3835. PMID 9892845.
  9. ↑ Håkansson, Marie-Louise; Brown, Hilary; Ghilardi, Nico; Skoda, Radek C.; Meister, Björn (1998-01-01). "Leptin Receptor Immunoreactivity in Chemically Defined Target Neurons of the Hypothalamus". Journal of Neuroscience. 18 (1): 559–572. ISSN 0270-6474. PMID 9412531.
  10. ↑ Kasagi, Yoko; Tokita, Reiko; Nakata, Tomoko; Imaki, Toshihiro; Minami, Shiro (2004-04-01). "Human growth hormone induces SOCS3 and CIS mRNA increase in the hypothalamic neurons of hypophysectomized rats". Endocrine Journal. 51 (2): 145–154. ISSN 0918-8959. PMID 15118263.
This article is issued from Wikipedia - version of the 11/23/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.